A researcher is interested in finding a 90% confidence interval for the mean number of times per

day that college students text. The study included 147 students who averaged 44.7 texts per

day. The standard deviation was 17.9 texts. Round answers to 3 decimal places where possible.

a. To compute the confidence interval use a tv distribution.

b. With 90% confidence the population mean number of texts per day is between

and

texts.

Answers

Answer 1

Answer:

90% confidence the Population mean number of texts per day

(42.2561 ,47.1439)

Step-by-step explanation:

Step(i):-  

Given sample size 'n' = 147

mean of the sample size x⁻ = 44.7

standard deviation of the sample 'S' = 17.9

90% confidence the Population mean number of texts per day

[tex](x^{-} - t_{\alpha } \frac{S}{\sqrt{n} } ,(x^{-} + t_{\alpha } \frac{S}{\sqrt{n} })[/tex]

Step(ii):-

Degrees of freedom

       ν=n-1=147-1=146

t₀.₁₀ =  1.6554

[tex](x^{-} - t_{\alpha } \frac{S}{\sqrt{n} } ,(x^{-} + t_{\alpha } \frac{S}{\sqrt{n} })[/tex]

[tex](44.7 - 1.6554 \frac{17.9}{\sqrt{147} } ,(44.7 + 1.6554 \frac{17.9}{\sqrt{147} })[/tex]

(44.7 - 2.4439 ,44.7 + 2.4439 )

(42.2561 ,47.1439)

Conclusion:-

90% confidence the Population mean number of texts per day

(42.2561 ,47.1439)


Related Questions

Because she has limited shelf space, she can't put out all her copies of the CD at once. On Monday morning, she stocked the display with 40 copies. By the end of the day, some of the copies had been sold. On Tuesday morning, she counted the number of copies left and then added that many more to the shelf. In other words, she doubled the number that was left in the display. At the end of the day, she discovered that she had sold the exact same number of copies as had been sold on Monday. On Wednesday morning, the manager decided to triple the number of copies that had been left in the case after Tuesday. Amazingly, she sold the same number of copies on Wednesday as she had on each of the first two days! But this time, at the end of the day the display case was empty.

Answers

Now, it look like there is some information missing in the answer. The whole problem should look like this:

Alicia Keys's new album As I Am is climbing the charts, and the manager of Tip Top Tunes expects to sell a lot of copies. Because she has limited shelf space, she can't put out all her copies of the CD at once. On Monday morning, she stocked the display with 40 copies. By the end of the day, some of the copies had been sold. On Tuesday morning, she counted the number of copies left and then added that many more to the shelf. In other words, she doubled the number that was left in the display. At the end of the day, she discovered that she had sold the exact same number of copies as had been sold on Monday. On Wednesday morning, the manager decided to triple the number of copies that had been left in the case after Tuesday. Amazingly, she sold the same number of copies on Wednesday as she had on each of the first two days! But this time, at the end of the day the display case was empty. How many copies of the As I Am CD did she sell each day?

Answer:

She sold 24 copies of the cd each day.

Step-by-step explanation:

In order to solve this problem we must first set our variable up. In this case, since we need to know what the number of sold cd's per day is, that will just be our variable:

x= Number of copies sold.

So we can start setting our equation up. So we take the first part of the problem:

"On Monday morning, she stocked the display with 40 copies. By the end of the day, some of the copies had been sold."

This can be translated as:

40-x

where this expression represents the number of copies left on the shelf by the end of monday.

"On Tuesday morning, she counted the number of copies left and then added that many more to the shelf."

so we represent it like this:

(40-x)+(40-x)

"In other words, she doubled the number that was left in the display."

so the previous expression can be simplified like this:

2(40-x)

"At the end of the day, she discovered that she had sold the exact same number of copies as had been sold on Monday."

so the expression now turns to:

2(40-x)-x   this is the number of copies left by the end of tuesday.

"On Wednesday morning, the manager decided to triple the number of copies that had been left in the case after Tuesday."

this translates to:

3[2(40-x)-x]

This is the number of copies on the shelf by the begining of Wednesday.

"Amazingly, she sold the same number of copies on Wednesday as she had on each of the first two days! But this time, at the end of the day the display case was empty."

this piece of information lets us finish writting our equation:

3[2(40-x)-x] -x = 0

since there were no copies left on the shelf, then the equation is equal to zero.

So now we proceed and solve the equation for x:

3[2(40-x)-x] -x = 0

We simplify it from the inside to the outside.

3[80-2x-x]-x=0

3[80-3x]-x = 0

we now distribute the 3 so we get:

240-9x-x=0

we combine like terms so we get:

240-10x=0

we move the 240 to the other side of the equation so we get:

-10x=-240

and divide both sides into -10 so we get:

x=24

so she sold 24 copies each day.

Calcule o valor de x nas equações literais: a) 5x – a = x+ 5a b) 4x + 3a = 3x+ 5 c) 2 ( 3x -a ) – 4 ( x- a ) = 3 ( x + a ) d) 2x/5 - (x-2a)/3 = a/2 Resolva as equações fracionárias: a) 3/x + 5/(x+2) = 0 , U = R - {0,-2} b) 7/(x-2) = 5/x , U = R - {0,2} c) 2/(x-3) - 4x/(x²-9) = 7/(x+3) , U = R - {-3,3}

Answers

Answer:

1) a) [tex]x = \frac{3}{2}\cdot a[/tex], b) [tex]x = 5-3\cdot a[/tex], c) [tex]x = -a[/tex], d) [tex]x = \frac{5}{2}\cdot a[/tex]

2) a) [tex]x = -\frac{3}{4}[/tex], b) [tex]x = -5[/tex], c) [tex]x = 3[/tex]

Step-by-step explanation:

1) a) [tex]5\cdot x - a = x + 5\cdot a[/tex]

[tex]5\cdot x - x = 5\cdot a + a[/tex]

[tex]4\cdot x = 6\cdot a[/tex]

[tex]x = \frac{3}{2}\cdot a[/tex]

b) [tex]4\cdot x + 3\cdot a = 3\cdot x + 5[/tex]

[tex]4\cdot x - 3\cdot x = 5 - 3\cdot a[/tex]

[tex]x = 5-3\cdot a[/tex]

c) [tex]2\cdot (3\cdot x - a) - 4\cdot (x-a) = 3\cdot (x+a)[/tex]

[tex]6\cdot x -2\cdot a -4\cdot x +4\cdot a = 3\cdot x +3\cdot a[/tex]

[tex]6\cdot x -4\cdot x -3\cdot x = 3\cdot a -4\cdot a +2\cdot a[/tex]

[tex]-x = a[/tex]

[tex]x = -a[/tex]

d) [tex]\frac{2\cdot x}{5} - \frac{x-2\cdot a}{3} = \frac{a}{2}[/tex]

[tex]\frac{6\cdot x-5\cdot (x-2\cdot a)}{15} = \frac{a}{2}[/tex]

[tex]\frac{6\cdot x - 5\cdot x+10\cdot a}{15} = \frac{a}{2}[/tex]

[tex]2\cdot (x+10\cdot a) = 15 \cdot a[/tex]

[tex]2\cdot x = 5\cdot a[/tex]

[tex]x = \frac{5}{2}\cdot a[/tex]

2) a) [tex]\frac{3}{x} + \frac{5}{x+2} = 0[/tex]

[tex]\frac{3\cdot (x+2)+5\cdot x}{x\cdot (x+2)} = 0[/tex]

[tex]3\cdot (x+2) + 5\cdot x = 0[/tex]

[tex]3\cdot x +6 +5\cdot x = 0[/tex]

[tex]8\cdot x = - 6[/tex]

[tex]x = -\frac{3}{4}[/tex]

b) [tex]\frac{7}{x-2} = \frac{5}{x}[/tex]

[tex]7\cdot x = 5\cdot (x-2)[/tex]

[tex]7\cdot x = 5\cdot x -10[/tex]

[tex]2\cdot x = -10[/tex]

[tex]x = -5[/tex]

c) [tex]\frac{2}{x-3}-\frac{4\cdot x}{x^{2}-9} = \frac{7}{x+3}[/tex]

[tex]\frac{2}{x-3} - \frac{4\cdot x}{(x+3)\cdot (x-3)} = \frac{7}{x+3}[/tex]

[tex]\frac{1}{x-3}\cdot \left(2-\frac{4\cdot x}{x+3} \right) = \frac{7}{x+3}[/tex]

[tex]\frac{x+3}{x-3}\cdot \left[\frac{2\cdot (x+3)-4\cdot x}{x+3} \right] = 7[/tex]

[tex]\frac{2\cdot (x+3)-4\cdot x}{x-3} = 7[/tex]

[tex]2\cdot (x+3) -4\cdot x = 7\cdot (x-3)[/tex]

[tex]2\cdot x + 6 - 4\cdot x = 7\cdot x -21[/tex]

[tex]2\cdot x - 4\cdot x -7\cdot x = -21-6[/tex]

[tex]-9\cdot x = -27[/tex]

[tex]x = 3[/tex]

what does 7g equal in like a verbal form

Answers

Answer:

see below

Step-by-step explanation:

7g can be "split" as 7 * g. The "*" means multiplication so a verbal form of this expression could be "7 times a number g" or "The product of 7 and a number g".

Activity 12-4: A large monohybrid crossa corn ear with purple and yellow kernels The total number of purple and yellow kernels on 8 different corn ears were counted: Purple kernels 3593 Yellow kernels 1102 What is the ratio of purple kernels to yellow kernels

Answers

Complete Question

The  complete question is shown on the first uploaded image

Answer:

  The correct option is C

Step-by-step explanation:

From the question we are told that

      The  number of purple  kernel is  [tex]n_k = 3593[/tex]

        The number of  yellow kernel is  [tex]n_y = 1102[/tex]

Generally the ration of the purple to the yellow kernels is mathematically evaluated as

              [tex]r = \frac{n_k}{n_y}[/tex]

substituting values

              [tex]r = \frac{3593}{1102}[/tex]

              [tex]r = 3.3[/tex]      

              [tex]r \approx 3[/tex]

Therefore the ratio is  

               [tex]1 \ Yellow : 3 \ Purple[/tex]

y varies directly as z, y=180, z=10 , find ywhen z=14

Answers

y = 252

Step-by-step explanation:

To find the value of y when z = 14 we must first find the relationship between them

The statement

y varies directly as z is written as

y = kz

where k is the constant of proportionality

when y = 180

z = 10

180 = 10k

Divide both sides by 10

k = 18

The formula for the variation is

y = 18z

When z = 14

y = 18(14)

y = 252

Hope this helps you

When a number is doubled and the
result is decreased by 4 the answer
is 19. Find the number.

Answers

Answer:

7.5

Step-by-step explanation:

Please help me guys :)
Question:
In exercises 1 through 4, find the one-sided limits lim x->2(left) f(x) and limx-> 2(right) from the given graph of f and determine whether lim x->2 f(x) exists.​

Answers

Step-by-step explanation:

For a left-hand limit, we start at the left side and move right, and see where the function goes as we get close to the x value.

For a right-hand limit, we start at the right side and move left, and see where the function goes as we get close to the x value.

If the two limits are equal, then the limit exists.  Otherwise, it doesn't.

1.  As we approach x = 2 from the left, f(x) approaches -2.

lim(x→2⁻) f(x) = -2

As we approach x = 2 from the right, f(x) approaches 1.

lim(x→2⁺) f(x) = 1

The limits are not the same, so the limit does not exist.

lim(x→2) f(x) = DNE

2. As we approach x = 2 from the left, f(x) approaches 4.

lim(x→2⁻) f(x) = 4

As we approach x = 2 from the right, f(x) approaches 2.

lim(x→2⁺) f(x) = 2

The limits are not the same, so the limit does not exist.

lim(x→2) f(x) = DNE

3. As we approach x = 2 from the left, f(x) approaches 2.

lim(x→2⁻) f(x) = 2

As we approach x = 2 from the right, f(x) approaches 2.

lim(x→2⁺) f(x) = 2

The limits are equal, so the limit exists.

lim(x→2) f(x) = 2

4. As we approach x = 2 from the left, f(x) approaches 2.

lim(x→2⁻) f(x) = 2

As we approach x = 2 from the right, f(x) approaches infinity.

lim(x→2⁺) f(x) = ∞

The limits are not the same, so the limit does not exist.

lim(x→2) f(x) = DNE

Change the polar coordinates (r, θ) to rectangular coordinates (x, y):(-2,sqrt2pi

Answers

Step-by-step explanation:

x=rcosθandy=rsinθ,. 7.7. r2=x2+y2andtanθ=yx. 7.8. These formulas can be used to convert from rectangular to polar or from polar to rectangular coordinates.

A hot metal bar is submerged in a large reservoir of water whose temperature is 60°F. The temperature of the bar 20 s after submersion is 120°F. After 1 min submerged, the temperature has cooled to 100°F. (Let y be measured in degrees Fahrenheit, and t be measured in seconds.) (a) Determine the cooling constant k. k = s−1 (b) What is the differential equation satisfied by the temperature y(t)? (Use y for y(t).) y'(t) = (c) What is the formula for y(t)? y(t) = (d) Determine the temperature of the bar at the moment it is submerged. (Round your answer to one decimal place.)

Answers

Answer:

a.  k = -0.01014 s⁻¹

b.  [tex]\mathbf{\dfrac{dy}{dt} = - \dfrac{In(\dfrac{3}{2})}{40}(y-60)}[/tex]

c.  [tex]\mathbf{y(t) = 60+ \dfrac{60 \sqrt{3}}{\sqrt{2}} \ e^{\dfrac{-In(\dfrac{3}{2})\ t}{40}}}[/tex]

d.  y(t) = 130.485°F

Step-by-step explanation:

A hot metal bar is submerged in a large reservoir of water whose temperature is 60°F. The temperature of the bar 20 s after submersion is 120°F. After 1 min submerged, the temperature has cooled to 100°F.

(Let y be measured in degrees Fahrenheit, and t be measured in seconds.)

We are to determine :

a.  Determine the cooling constant k. k = s−1

By applying the new law of cooling

[tex]\dfrac{dT}{dt} = k \Delta T[/tex]

[tex]\dfrac{dT}{dt} = k(T_1-T_2)[/tex]

[tex]\dfrac{dT}{dt} = k (T - 60)[/tex]

Taking the integral.

[tex]\int \dfrac{dT}{T-60} = \int kdt[/tex]

㏑ (T -60) = kt + C

T - 60 = [tex]e^{kt+C}[/tex]

[tex]T = 60+ C_1 e^{kt} ---- (1)[/tex]

After 20 seconds, the temperature of the bar submersion is 120°F

T(20) = 120

From equation (1) ,replace t = 20s and T = 120

[tex]120 = 60 + C_1 e^{20 \ k}[/tex]

[tex]120 - 60 = C_1 e^{20 \ k}[/tex]

[tex]60 = C_1 e^{20 \ k} --- (2)[/tex]

After 1 min i.e 60 sec , the temperature  = 100

T(60) = 100

From equation (1) ; replace t = 60 s and T = 100

[tex]100 = 60 + c_1 e^{60 \ t}[/tex]

[tex]100 - 60 =c_1 e^{60 \ t}[/tex]

[tex]40 =c_1 e^{60 \ t} --- (3)[/tex]

Dividing equation (2) by (3) , we have:

[tex]\dfrac{60}{40} = \dfrac{C_1e^{20 \ k } }{C_1 e^{60 \ k}}[/tex]

[tex]\dfrac{3}{2} = e^{-40 \ k}[/tex]

[tex]-40 \ k = In (\dfrac{3}{2})[/tex]

- 40 k = 0.4054651

[tex]k = - \dfrac{0.4054651}{ 40}[/tex]

k = -0.01014 s⁻¹

 

b. What is the differential equation satisfied by the temperature y(t)?

Recall that :

[tex]\dfrac{dT}{dt} = k \Delta T[/tex]

[tex]\dfrac{dT}{dt} = \dfrac{- In (\dfrac{3}{2})}{40}(T-60)[/tex]

Since y is the temperature of the body , then :

[tex]\mathbf{\dfrac{dy}{dt} = - \dfrac{In(\dfrac{3}{2})}{40}(y-60)}[/tex]

(c) What is the formula for y(t)?

From equation (1) ;

where;

[tex]T = 60+ C_1 e^{kt} ---- (1)[/tex]

Let y be measured in degrees Fahrenheit

[tex]y(t) = 60 + C_1 e^{-\dfrac{In (\dfrac{3}{2})}{40}t}[/tex]

From equation (2)

[tex]C_1 = \dfrac{60}{e^{20 \times \dfrac{-In(\dfrac{3}{2})}{40}}}[/tex]

[tex]C_1 = \dfrac{60}{e^{-\dfrac{1}{2} {In(\dfrac{3}{2})}}}[/tex]

[tex]C_1 = \dfrac{60}{e^ {In(\dfrac{3}{2})^{-1/2}}}}[/tex]

[tex]C_1 = \dfrac{60}{\sqrt{\dfrac{2}{3}}}[/tex]

[tex]C_1 = \dfrac{60 \times \sqrt{3}}{\sqrt{2}}}[/tex]

[tex]\mathbf{y(t) = 60+ \dfrac{60 \sqrt{3}}{\sqrt{2}} \ e^{\dfrac{-In(\dfrac{3}{2})\ t}{40}}}[/tex]

(d) Determine the temperature of the bar at the moment it is submerged.

At the moment it is submerged t = 0

[tex]\mathbf{y(0) = 60+ \dfrac{60 \sqrt{3}}{\sqrt{2}} \ e^{\dfrac{-In(\dfrac{3}{2})\ 0}{40}}}[/tex]

[tex]\mathbf{y(t) = 60+ \dfrac{60 \sqrt{3}}{\sqrt{2}} }[/tex]

y(t) = 60 + 70.485

y(t) = 130.485°F

4(x/2-2) > 2y-11 which of the following inequalities is equivalent to the inequality above?
1) 4x+2y-3 > 0
2) 4x-2y+3 > 0
3) 2x+2y-3 > 0
4) 2x-26+3 > 0

Answers

4) 2x-2y+3 > 0

although it is spelt "26" on the choices

It is advertised that the average braking distance for a small car traveling at 65 miles per hour equals 122 feet. A transportation researcher wants to determine if the statement made in the advertisement is false. She randomly test drives 38 small cars at 65 miles per hour and records the braking distance. The sample average braking distance is computed as 116 feet. Assume that the population standard deviation is 21 feet. (You may find it useful to reference the appropriate table: z table or t table) a. State the null and the alternative hypotheses for the test.

Answers

Complete Question

The complete question is shown on the first uploaded image

Answer:

the null hypothesis is  [tex]H_o : \mu = 122[/tex]

the alternative hypothesis is [tex]H_a : \mu \ne 122[/tex]

The test statistics is  [tex]t = - 1.761[/tex]

The p-value is  [tex]p = P(Z < t ) = 0.039119[/tex]

so

    [tex]p \ge 0.01[/tex]

Step-by-step explanation:

From the question we are told that

   The population mean is  [tex]\mu = 122[/tex]

     The sample size is  n=  38

    The sample mean is  [tex]\= x = 116 \ feet[/tex]

     The standard deviation is [tex]\sigma = 21[/tex]

     

Generally the null hypothesis is  [tex]H_o : \mu = 122[/tex]

                the alternative hypothesis is [tex]H_a : \mu \ne 122[/tex]

Generally the test statistics is mathematically evaluated as

         [tex]t = \frac { \= x - \mu }{\frac{ \sigma }{ \sqrt{n} } }[/tex]

substituting values

         [tex]t = \frac { 116 - 122 }{\frac{ 21 }{ \sqrt{ 38} } }[/tex]

         [tex]t = - 1.761[/tex]

The p-value is mathematically represented as

      [tex]p = P(Z < t )[/tex]

From the z- table  

     [tex]p = P(Z < t ) = 0.039119[/tex]

So  

     [tex]p \ge 0.01[/tex]

 

         

     

           

5 STARS IF CORRECT! In general, Can you translate a phrase or sentence into symbols? Explain the answer.

Answers

Answer:

Step-by-step explanation:

I answered this already a few minutes ago.

Answer:

yes you can

Step-by-step explanation:

you can write algebraic expressions and use variables for the unknown

Amy is a software saleswoman. Let Y represent her total pay (in dollars). Let X represent the number of copies of "English is Fun" she sells. Suppose that X and Y are related by the equation 110X +2300 = Y.

Answer the questions below. Note that a change can be an increase or decrease.

What is the change in Amy's total pay for each copy of "English is Fun"?

What is Amy's total pay if she doesn't sell any copies of "English is Fun"?​

Answers

Answer:

1) For every copy she sells, her pay increases by $110

2) Her total pay is 2300

Step-by-step explanation:

1) X is the number of copies she sells. In the equation 110X+ 2300 = Y, X will determine how many times 110 is multiplied. So, for every increase by one in X, Y will also go up by 110

eg.

110(50) + 2300 = 7800   -- if she sells 50 copies

110(51) + 2300 = 7910  -- if she sells 51 copies,

2) If she doesn't sell any copies, the equation becomes 110 * 0 + 2300. Anything multiplied by 0 equals 0, so the equation equals 0 + 2300 = 2300 = Y

Therefore, if she doesn't sell any copies, she will get a pay of $2300  

Your job in a company is to fill quart-size bottles of oil from a full -gallon oil tank. Then you are to pack quarts of oil in a case to ship to a store. How many full cases of oil can you get from a full -gallon tank of oil?

Answers

Answer:

See below.

Step-by-step explanation:

1 gal = 4 qt

With a full gallon oil tank, you can fill 4 1-qt bottles.

The problem does not mention the number of quarts that go in a case, so there is not enough information to answer the question.

Also, is the full tank really only 1 gallon, or is there a number missing there too?

The numbers of words defined on randomly selected pages from a dictionary are shown below. Find the mean, median, mode of the listed numbers. 72 58 62 38 44 66 42 49 76 52 What is the mean? Select the correct choice below and ,if necessary ,fill in the answer box within your choice.(around to one decimal place as needed)

Answers

Answer:

Mean: 55.9

Median: 55

Mode: None

Step-by-step explanation:

First, find the mean by dividing the sum by the number of elements:

(72 + 58 + 62 + 38 + 44 + 66 + 42 + 49 + 76 + 52) / 10

= 55.9

Next, find the median by putting the numbers in order and finding the middle one:

38, 42, 44, 49, 52, 58, 62, 66, 72, 76

There is no middle number, so we will take the average of 52 and 58, which is 55.

Lastly, to find the mode, we have to find the number that occurs the most.

All of the numbers occur one time, so there is no mode.

An economist is interested in studying the income of consumers in a particular region. The population standard deviation is known to be $1,000. A random sample of 50 individuals resulted in an average income of $15,000. What is the width of the 90% confidence interval

Answers

Answer:

The width is  [tex]w = 282.8[/tex]

Step-by-step explanation:

From the question we are told that

  The sample size is n =  50

  The  population standard deviation is  [tex]\sigma = \$ 1000[/tex]

   The sample size is  [tex]\= x = \$ 15,000[/tex]

Given that the confidence level is  90%  then the level of significance can be mathematically represented as

             [tex]\alpha = 100 - 90[/tex]  

             [tex]\alpha = 10 \%[/tex]  

              [tex]\alpha = 0.10[/tex]

Next we obtain the critical value of  [tex]\frac{\alpha }{2}[/tex] from the  normal distribution table, the value is  

             [tex]Z_{\frac{0.10 }{2} } = 1.645[/tex]

Generally the margin of error is mathematically represented as

               [tex]E = Z_{\frac{0.10}{2} } * \frac{\sigma }{\sqrt{n} }[/tex]

substituting values

                 [tex]E = 1.645 * \frac{1000 }{\sqrt{50 }}[/tex]

=>                [tex]E = 141.42[/tex]

  The width of the 90%  confidence level is mathematically represented as

                      [tex]w = 2 * E[/tex]

substituting values

                       [tex]w = 2 * 141.42[/tex]

                       [tex]w = 282.8[/tex]

 

Mr Osei has a rectangular field measured 85m long and 25m wide. How long is the distance around the field?

Answers

Answer:

220m

Step-by-step explanation:

l=85m

b=25m

perimeter=2(l+b)

2(85+25)

2(110)

=220m

perimeter is 220m

Answer:

Distance around the field is 220m

Step-by-step explanation:

The distance around the field means the perimeter of the field

Since the field is rectangular

Perimeter of a rectangle = 2l + 2w

where l is the length

w is the width

From the question

l = 85m

w = 25m

Perimeter = 2(85) + 2(25)

Perimeter = 170 + 50

The final answer is

Perimeter = 220m

Hope this helps you

A United Nations report shows the mean family income for Mexican migrants to the United States is $26,500 per year. A FLOC (Farm Labor Organizing Committee) evaluation of 24 Mexican family units reveals a mean to be $30,150 with a sample standard deviation of $10,560. State the null hypothesis and the alternate hypothesis.

Answers

Answer:

The null hypothesis [tex]\mathtt{H_0 : \mu = 26500}[/tex]

The alternative hypothesis [tex]\mathtt{H_1 : \mu \neq 26500}[/tex]

Step-by-step explanation:

The summary of the given statistics is:

Population Mean = 26,500

Sample Mean = 30,150

Standard deviation = 10560

sample size = 24

The objective is to state the null hypothesis and the alternate hypothesis.

An hypothesis is a claim with  insufficient information which tends to be challenged into  further testing and experimentation in order to determine if such claim is significant or not.

The null hypothesis is a default hypothesis where there is no statistical significance between the two variables in the hypothesis.

The alternative hypothesis is the research hypothesis that the  researcher is trying to prove.

The null hypothesis [tex]\mathtt{H_0 : \mu = 26500}[/tex]

The alternative hypothesis [tex]\mathtt{H_1 : \mu \neq 26500}[/tex]

The test statistic can be  computed as follows:

[tex]z = \dfrac{\overline X - \mu}{\dfrac{\sigma}{\sqrt{n}}}[/tex]

[tex]z = \dfrac{30150 - 26500}{\dfrac{10560}{\sqrt{24}}}[/tex]

[tex]z = \dfrac{3650}{\dfrac{10560}{4.8989}}[/tex]

[tex]z = \dfrac{3650 \times 4.8989 }{{10560}}[/tex]

z = 1.6933

which polynomial correctly combines the like terms and expresses the given polynomial in standard form? 9xy³ -4y⁴ -10x²y² + x³y + 3x⁴ + 2x²y² - 9y⁴

Answers

Answer:

3x^4+(x^3)y-8x^2y^2+9xy^3-13y^4

Step-by-step explanation:

3x^4+(nothing)=3x^4

x^3y+(nothing)=x^3y

-10x^2y^2=2x^2y^2=-8x^2y^2

9xy^3+(nothing)=0

-4y^4-9y^4=-13y^4

Add it all up and write the terms by descending order of exponent value, and u get my answer.

What is the equation of the parabola that has its vertex at (8,-1) and a y-intercept of (0,-17)?

Answers

y = a(x  + 1.5)^2 - 12.5

y intercept is (0,-8) so:-

-8 = a(0+1.5)^2 - 12.5

-8 = 2.25a - 12.5

a =  4.5/ 2.25 = 2

so we have  

y  = 2 ( x +1.5)^2 - 12.5

solving for x  when y = 0:-

(x + 1.5)^2 = 12.5/2 = 6.25

taking sqrt's  x + 1.5  = +/- 2.5

x =  -4,   1

so the x intercepts are (-4,0) and (1,0)

Answer:

y = –1∕4(x – 8)^2 – 1

Step-by-step explanation:

I took the exam and  got  it  right.

Yuko added a 15 percent tip when she paid her cab driver. If the fare was $25.50, what was the total amount she paid? A. $28 B. $30 C. $31

Answers

Answer:

B. $30

Step-by-step explanation:

First, find the amount of the tip.

Multiply the tip rate and taxi fare.

tip rate * taxi fare

The tip rate is 15% and the taxi fare is $25.50

15% * 25.50

Convert 15% to a decimal. Divide 15 by 100 or move the decimal place two spots to the left.

15/100=0.15

15.0 ---> 1.5 ---> 0.15

0.15 * 25.50

3.825

The tip amount is $3.825

Next, find the total amount she paid.

Add the taxi fare and the tip amount.

taxi fare + tip amount

The taxi fare is $25.50 and the tip amount is $3.825

$25.50 + $3.825

$29.325

Round to the nearest dollar. Typically, this would round down to $29, but that is not an answer choice. So, if we round up, the next best answer is $30.

Therefore, the best answer choice is B. $30

Which option is correct and how would one solve for it?

Answers

Answer:

28

Step-by-step explanation:

We need to find the value of [tex]\Sigma_{x=0}^3\ 2x^2[/tex]

We know that,

[tex]\Sigma n^2=\dfrac{n(n+1)(2n+1)}{6}[/tex]

Here, n = 3

So,

[tex]\Sigma n^2=\dfrac{3(3+1)(2(3)+1)}{6}\\\\\Sigma n^2=14[/tex]

So,

[tex]\Sigma_{x=0}^3\ 2x^2=2\times 14\\\\=28[/tex]

So, the value of [tex]\Sigma_{x=0}^3\ 2x^2[/tex] is 28. Hence, the correct option is (d).

graph the solution set to the inequality

Answers

Graphed using the given range equation. The shaded area is the possible range, extending to infinity, infinity from 0, -1.

Please help helppp :((((

Answers

Answer:

m∠Q = 61°

m∠S = 61°

m∠R = 58°

Step-by-step explanation:

Since we have an isosceles triangle, we know that ∠Q and ∠S are congruent.

Step 1: Definition of isosceles triangle

2x + 41 = 3x + 31

41 = x + 31

x = 10

Step 2: Find m∠Q

m∠Q = 2(10) + 41

m∠Q = 20 + 41

m∠Q = 61°

Step 3: Find m∠S

Since m∠Q = m∠S,

m∠S = 61°

Step 4: Find m∠R (Definition of a triangle)

Sum of angles in a triangle adds up to 180°

m∠R = 180 - (61 + 61)

m∠R = 180 - 122

m∠R = 58°

Based on a​ poll, 40​% of adults believe in reincarnation. Assume that 4 adults are randomly​ selected, and find the indicated probability. Complete parts​ (a) through​ (d) below.Required:a. The probability that exactly 3 of the 4 adults believe in reincarnation is? b. The probability that all of the selected adults believe in reincarnation is? c. The probability that at least 3 of the selected adults believe in reincarnation is? d. If 4 adults are randomly​selected, is 3 a significantly high number who believe in​reincarnation?

Answers

Complete Question

The complete question is shown on the first uploaded image

Answer:

a

    [tex]P(3) = 0.154[/tex]

b

    [tex]P(4) = 0.026[/tex]

c

   [tex]P( X \ge 3 ) = 0.18[/tex]

d

   option C is correct

Step-by-step explanation:

From the question we are told that

      The probability of success is  p =  0.4

      The sample size is n=  4

 This adults believe follow a binomial distribution is because there are only two outcome one is an adult  believes in  reincarnation and the second an adult does not believe in reincarnation

  The probability of  failure is mathematically evaluated as

              [tex]q = 1 - p[/tex]

substituting values

             [tex]q = 1 - 0.4[/tex]

             [tex]q = 0.6[/tex]

Considering a  

The  probability that exactly 3 of the selected adults believe in reincarnation is mathematically represented as

       [tex]P(3) = \left n} \atop {}} \right. C_ 3 * p^3 * q^{n-3}[/tex]

substituting values

     [tex]P(3) = \left 4} \atop {}} \right. C_ 3 * (0.40)^3 * (0.60)^{4-3}[/tex]

Here [tex]\left 4} \atop {}} \right.C_3[/tex] means  4  combination 3 . i have calculated this using a calculator and the value is  

           [tex]\left 4} \atop {}} \right.C_3 = 4[/tex]

So

         [tex]P(3) = 4* (0.4)^3 * (0.6)[/tex]

          [tex]P(3) = 0.154[/tex]

Considering b

The probability that all of the selected adults believe in reincarnation is mathematically represented as

        [tex]P(n) = \left n} \atop {}} \right. C_ n * p^n * q^{n-n}[/tex]

substituting values

         [tex]P(4) = \left 4} \atop {}} \right. C_ 4 * (0.40)^4 * (0.60)^{4-4}[/tex]

Here [tex]\left 4} \atop {}} \right.C_3[/tex] means  4  combination  . i have calculated this using a calculator and the value is  [tex]\left 4} \atop {}} \right.C_4 = 1[/tex]

so

          [tex]P(4) = 1* (0.4)^4 * 1[/tex]

=>       [tex]P(4) = 0.026[/tex]

Considering c

the probability that at least 3 of the selected adults believe in reincarnation is mathematically represented as

     [tex]P( X \ge 3 ) = P(3 ) + P(n )[/tex]

substituting values

    [tex]P( X \ge 3 ) = 0.154 + 0.026[/tex]

     [tex]P( X \ge 3 ) = 0.18[/tex]

From the calculation the probability that all the 4 randomly selected persons believe in reincarnation is  [tex]p(4) = 0.026 < 0.05[/tex]

But the the probability of 3 out of the 4 randomly selected person believing in reincarnation is [tex]P(3) = 0.154 \ which \ is \ > 0.05[/tex]

Hence 3 is not a  significantly high number of adults who believe in reincarnation because the probability that 3 or more of the selected adults believe in reincarnation is greater than 0.05.

If a cube has an edge of 2 feet. The edge is increasing at the rate of 6 feet per minute. How would i express the volume of the cube as a function of m, the number of minutes elapsed. V(m)= ??

Answers

Answer:

v(m) = 8 + 48m+ 180m² +216m³

Step-by-step explanation:

Let's first of all represent the edge of the the cube as a function of minutes.

Initially the egde= 2feet

As times elapsed , it increases at the rate of 6 feet per min, that is, for every minute ,there is a 6 feet increase.

Let the the egde be x

X = 2 + 6(m)

Where m represent the minutes elapsed.

So we Al know that the volume of an edge = edge³

but egde = x

V(m) = x³

but x= 2+6(m)

V(m) = (2+6m)³

v(m) = 8 + 48m+ 180m² +216m³

The volume of cube as function of m is,   [tex]V(m)=72m[/tex]

Let us consider that edge of cube is a feet.

Since,   The edge is increasing at the rate of 6 feet per minute.

                      [tex]\frac{da}{dt}=6feet/min.[/tex]

Volume of cube , V = [tex]a^{3}[/tex]

            [tex]\frac{dV}{dt} =3a^{2} \frac{da}{dt}[/tex]

Substituting the value of  da/dt in above equation.

We get,     [tex]\frac{dV}{dt}=3a^{2}*(6) =18a^{2} \\\\dV=18a^{2}dt[/tex]

Integrating on both side.

          [tex]V=18a^{2}t[/tex]

Since, number of minutes elapsed is m.

Substitute , t = m and a = 2 feet in above equation.

We get,     [tex]V=18(2)^{2}*m=72m[/tex]

Thus, the volume of cube as function of m is,   [tex]V(m)=72m[/tex]

Learn more:

https://brainly.com/question/14002029

please answer this question please ​

Answers

Answer:Amount = Rs 13891.50Compound interest = Rs 1891.50

Step-by-step explanation:

C = Amount (A) - Principal (P)

Where

C is the compound interest

To find the amount we use the formula

[tex]A = P ({1 + \frac{r}{100} })^{n} [/tex]

where

P is the principal

r is the rate

n is the period / time

From the question

P = Rs 12, 000

r = 5%

n = 3 years

Substitute the values into the above formula

That's

[tex]A = 12000 ({1 + \frac{5}{100} })^{3} \\ A = 12000(1 + 0.05)^{3} \\ A = 12000 ({1.05})^{3} [/tex]

We have the answer as

Amount = Rs 13891.50

Compound interest = 13891.50 - 12000

Compound interest = Rs 1891.50

Hope this helps you

A couple has a total household income of $84,000. The husband earns $18,000 less than twice what the wife earns. How much does the wife earn? Select the correct answer below:

Answers

Answer:

$34000

Step-by-step explanation:

We can set up a systems of equations, assuming [tex]h[/tex] is the husbands income and [tex]w[/tex] is the wife's income.

h + w = 84000

h = 2w - 18000

We can substitute h into the equation as 2w - 18000:

(2w - 18000) + w = 84000

Combine like terms:

3w - 18000 = 84000

Add 18000 to both sides

3w = 102000

And divide both sides by 3

w = 34000

Now that we know how much the wife earns, we can also find out how much the husband earns by substituting into the equation.

h + 34000  = 84000

h = 50000

Hope this helped!

Two balls are drawn in succession out of a box containing 5 red and 4 white balls. Find the probability that at least 1 ball was​ red, given that the first ball was (Upper A )Replaced before the second draw. (Upper B )Not replaced before the second draw. ​(A) Find the probability that at least 1 ball was​ red, given that the first ball was replaced before the second draw. StartFraction 24 Over 49 EndFraction ​(Simplify your answer. Type an integer or a​ fraction.) ​(B) Find the probability that at least 1 ball was​ red, given that the first ball was not replaced before the second draw.

Answers

Answer:

The answer is below

Step-by-step explanation:

The box contains 5 red and 4 white balls.

A) The probability that at least 1 ball was​ red = P(both are red) + P(first is red and second is white) + P(first is white second is red)

Given that the first ball was (Upper A )Replaced before the second draw:

P(both are red) = P(red) × P(red) = 5/9 × 5/9 = 25/81

P(first is red and second is white) = P(red) × P(white) = 5/9 × 4/9 = 20/81

P(first is white and second is red) = P(white) × P(red) = 4/9 × 5/9 = 20/81

The probability that at least 1 ball was​ red = 25/81 + 20/81 + 20/81 = 65/81

B) The probability that at least 1 ball was​ red = P(both are red) + P(first is red and second is white) + P(first is white second is red)

Given that the first ball was not Replaced before the second draw:

P(both are red) = P(red) × P(red) = 5/9 × 4/8 = 20/72 (since it was not replaced after the first draw the number of red ball remaining would be 4 and the total ball remaining would be 8)

P(first is red second is white) = P(red) × P(white) = 5/9 × 4/8 = 20/72

P(first is white and second is red) = P(white) × P(red) = 4/9 × 5/8 = 20/72

The probability that at least 1 ball was​ red = 20/72 + 20/72 + 20/72 = 60/72

f(x)=3x2+10x-25 g(x)=9x2-25 Find (f/g)(x).

Answers

Answer:

[tex](f/g)(x) = \frac{x + 5}{3x + 5} [/tex]

Step-by-step explanation:

f(x) = 3x² + 10x - 25

g(x) = 9x² - 25

To find (f/g)(x) divide f(x) by g(x)

That's

[tex](f/g)(x) = \frac{3 {x}^{2} + 10x - 25 }{9 {x}^{2} - 25 } [/tex]

Factorize both the numerator and the denominator

For the numerator

3x² + 10x - 25

3x² + 15x - 5x - 25

3x ( x + 5) - 5( x + 5)

(3x - 5 ) ( x + 5)

For the denominator

9x² - 25

(3x)² - 5²

Using the formula

a² - b² = ( a + b)(a - b)

(3x)² - 5² = (3x + 5)(3x - 5)

So we have

[tex](f/g)(x) = \frac{(3x - 5)(x + 5)}{(3x + 5)(3x - 5)} [/tex]

Simplify

We have the final answer as

[tex](f/g)(x) = \frac{x + 5}{3x + 5} [/tex]

Hope this helps you

Other Questions
A. Suppose two dice (one red, one green) are rolled. Consider the following events. A: the red die shows 1; B: the numbers add to 4; C: at least one of the numbers is 1; and D: the numbers do not add to 10. Express the given event in symbols. The red die shows 1 and the numbers add to 4.How many elements does it contain?B. Suppose two dice (one red, one green) are rolled. Consider the following events. A: the red die shows 3; B: the numbers add to 2; C: at least one of the numbers is 1; and D: the numbers do not add to 10. Express the given event in symbols. HINT [See Example 5.]The numbers do not add to 2.How many elements does it contain?C. Suppose two dice (one red, one green) are rolled. Consider the following events. A: the red die shows 1; B: the numbers add to 2; C: at least one of the numbers is 3; and D: the numbers do not add to 11. Express the given event in symbols. HINT [See Example 5.]Either the numbers add to 11 or the red die shows a 1.How many elements does it contain?D. Suppose two dice (one red, one green) are rolled. Consider the following events. A: the red die shows 4; B: the numbers add to 5; C: at least one of the numbers is 1; and D: the numbers do not add to 9. Express the given event in symbols. HINT [See Example 5.]Either the numbers add to 5, or they add to 9, or at least one of them is 1.How many elements does it contain? In a Young's double-slit experiment, a set of parallel slits with a separation of 0.102 mm is illuminated by light having a wavelength of 575 nm and the interference pattern observed on a screen 3.50 m from the slits.(a) What is the difference in path lengths from the two slits to the location of a second order bright fringe on the screen?(b) What is the difference in path lengths from the two slits to the location of the second dark fringe on the screen, away from the center of the pattern? You observe a portfolio for five years and determine that its average return is 11.3% and the standard deviation of its returns in 19.7%. Would a 30% loss next year be outside the 95% confidence interval for this portfolio? The Milankovitch cycles describe the change in ________ because of changes in the ________ of Earth relative to the Sun. You are the network administrator for your company. A user reports that he cannot access network resources from his computer. He was able to access the resources yesterday. While troubleshooting his computer, you find that his computer is issued an Automatic Private IP Addressing (APIPA) address. All the network equipment in the user's computer is functioning properly because you are able to access the user's computer from a remote computer. What is most likely the problem What does an AED do to restart the heart? Which of the following is not part of the solution to overfishing the world's oceans? Monitoring fishing activities by satellite Using nets with smaller mesh to catch more fish Exploring alternative sources of income for fishers Restricting fishing boats to only a few days per month how can an objects volume be determined using water displacement ? There are 100 prize tickets in a bowl, numbered 1 to 100. What is the probabilitythat an even numbered prize ticket will be chosen at random, not replaced, then anodd numbered prize ticket will be chosen? Does this represent an independent ordependent event? Explain. Where else in the bay area or elsewhere do you think would be an important place to dedicate as a wildlife corridor? Explain why? 8. (01.02)Given that f(x) = x2 + 2x + 3 and g(x)X+4.3solve for f(g(x)) when x = 2. 251133 The voucher system of control: Multiple Choice Is a set of procedures and approvals designed to control cash receipts and the acceptance of obligations. Establishes procedures for verifying, approving, and recording obligations for eventual cash disbursement. Establishes procedures for receiving checks for the sale of verified, approved, and recorded activities. Applies only when multiple purchases are made from the same supplier. Is required in large companies but not beneficial for small to mid-sized companies. HELP i need you guys to help find 6 things that you like about how the book "The Lottery" was written 2 + 8(x + 2) = 52a 3b 1C2d 4 Samuel, a longtime employee of the ABCD Corporation, was injured when he fell off a ladder while stocking widgets at ABDC at their East Lansing, Michigan location. Samuel believes ABCD Corporation was negligent for selling widgets. If Samuel sues his employer in a circuit court under a negligence theory of recovery:a. he will loseb. he will winc. he will forfeit his rights to workers compensation benefits, completelyd. he will forfeit his rights to workers compensation benefits, but only if the court awards him non-economic damages Although Python provides us with many list methods, it is good practice and very instructive to think about how they are implemented. Implement a Python methods that works like the following: a. count b. in: return True if the item is in the list c. reverse d. index: return -1 if the item is not in the list e. insert The process of estimating expected future cash flows of a project using only the relevant parts of the balance sheet and income statements is referred to as Which recovery method helps users boot into an environment to get them back into the system so they can begin the troubleshooting process Please help! Change 3/8 to a decimal fraction. name four points that are not coplanar