in a random sample of 28 people, the mean commute time to work was 31.2 minutes and the standard deviation was 7.3 minutes. assume the population is normally distributed and use a t-distribution to construct a 99% confidence interval for the population mean u. What is the margin of error of u

Answer:

The predicted final exam grade is 83

Step-by-step explanation:

Given

[tex]\bar x = 75[/tex] -- midterm mean

[tex]\sigma_x = 10[/tex] --- midterm standard deviation

[tex]\mu =75[/tex] --- final mean

[tex]\sigma = 10[/tex] --- final standard deviation

[tex]r = 0.8[/tex]

Required

The predicted final grade of student who score 85 in midterm

The prediction is represented as:

[tex]y = \alpha + \beta x[/tex]

Where:

[tex]\beta = r * \frac{\sigma}{\sigma_x}[/tex]

[tex]\beta = 0.8 * \frac{10}{10}[/tex]

[tex]\beta = 0.8 * 1[/tex]

[tex]\beta = 0.8[/tex]

and

[tex]\alpha = \mu - r * \bar x[/tex]

[tex]\alpha = 75- 0.8 * 75[/tex]

[tex]\alpha = 75- 60[/tex]

[tex]\alpha = 15[/tex]

So:

[tex]y = \alpha + \beta x[/tex]

[tex]y = 15 + 0.8x[/tex]

For a student who gets 85, the prediction is:

[tex]y = 15 + 0.8*85[/tex]

[tex]y = 15 + 68[/tex]

[tex]y = 83[/tex]

Answer:

Sylvia=16

brother=8

Step-by-step explanation:

8+7=15

16-1=15

Answer:

2y - 9

Step-by-step explanation:

number = y

2 × y - 9

2 × y can be simplified to 2y.

2y - 9

Answer:

We can write sin x in terms of tan x/2 using the formula:

⇒ sin x = (2 tan (x/2)) / (1 + tan2(x/2))

Therefore, using the above formula, we can find the values of tan x/2 by putting the value of sin x.

⇒ -4/5 = (2 tan (x/2)) / (1 + tan2(x/2))

Now, if we replace tan (x/2) by y, we get a quadratic equation:

⇒ 0.8y2 + 2y + 0.8 = 0

⇒ 2y2 + 5y + 2 = 0

By using the quadratic formula, we get y = -0.5, -2

Hence, the value of tan (x/2) = -0.5, -2

Now, we have two solutions of tan (x/2).

Now, let's check for the ideal solution using the formula tan x = (2 tan (x/2)) / (1 - tan2(x/2)).

For tan (x/2) = -0.5:

⇒ tan x = 2(-0.5) / 1 - (-0.5)2 = -4/3

It is also given that x lies in the third quadrant. We know that tan is positive in the third quadrant, and here we get tan x = -4/3 which is negative.

Hence, we can say that tan (x/2) = -0.5 is not a correct solution. Hence it is rejected.

Now let's check for tan (x/2) = -2.

⇒ tan x = 2(-2) / 1 - (-2)2 = 4/3

Here, we get tan x = 4/3 which is positive.

Hence, we can say that tan (x/2) = -2 is a correct solution.

[tex]\longrightarrow{\green{ D. \:3 {a}^{4} \sqrt{2a} }}[/tex] 

[tex]\large\mathfrak{{\pmb{\underline{\red{Step-by-step\:explanation}}{\red{:}}}}}[/tex]

[tex] \sqrt{18 {a}^{9} } \\ \\ ➝ \: \sqrt{2 \times 3 \times 3 \times {a}^{9} } \\ \\ ➝ \: \sqrt{2 \times ({3})^{2} \times {( {a}^{4}) }^{2} a } \\ \\ [∵( { {a}^{4} )}^{2} a = {a}^{4 \times 2 + 1} = {a}^{9}] \\ \\ ➝ \: 3 \times {a}^{4} \sqrt{2a} \\ \\ ➝ \: 3 {a}^{4} \sqrt{2a} [/tex]

[tex]\pink{\large\qquad \qquad \underline{ \pmb{{ \mathbb{ \maltese \: \: Mystique35}}}}}[/tex]

Answer:

The answer is [tex]3a^{4}\sqrt{2a}[/tex]

Step-by-step explanation:

To simplify the radical, start by factoring 9 out of 18 for step 1. Next, for step 2, rewrite 9 as [tex]3^{2}[/tex]. Then, factor out [tex]a^{8}[/tex] for step 3. For step 4, rewrite [tex]a^{8}[/tex] as [tex](a^{4})^{2}[/tex]. Then, for step 5, move the 2 in the radical. Rewrite [tex]3^{2}(a^{4})^{2}[/tex]as [tex](3a^{4})^{2}[/tex] for step 6. Then, add parentheses to the radical for step 7. Finally, for step 8 pull the terms out from under the radical, and the answer is [tex]3a^{4}\sqrt{2a}[/tex].  

Step 1: [tex]\sqrt{9(2)a^{9} }[/tex]

Step 2: [tex]\sqrt{3^{2}*2a^{9}[/tex]

Step 3:  [tex]\sqrt{3^{2}*2(a^{8}a) }[/tex]

Step 4: [tex]\sqrt{3^{2}*2((a^{4})^{2}) }[/tex]

Step 5: [tex]\sqrt{3^{2}(a^{4})^{2}*2a }[/tex]

Step 6: [tex]\sqrt{(3a^{4} )^{2}*2a }[/tex]

Step 7:  [tex]\sqrt{(3a^{4})^{2}*(2a) }[/tex]

Step 8: [tex]3a^{4}\sqrt{2a}[/tex]

Answer:

40x - 300,000

7,500

Step-by-step explanation:

profit  = revenue - cost

p(x) = 75x - (35x + 300,000)

p(x) = 40x - 300,000

Break even is when profit is zero

40x - 300,000 = 0

40x = 300,000

x = 7,500

The functions that represents the​ total-profit function would be p(x) = 40x - 300,000. so the correct option is A.

Function is a type of relation, or rule, that maps one input to specific single output.

Given that for a certain company ​C(x) =35x+300,000 represents; the total cost​ function, and ​R(x)=75x represents the total revenue function.

WE can calculate the profit by the following formula;

Profit  = revenue - cost

p(x) = 75x - (35x + 300,000)

p(x) = 40x - 300,000

Now Break even is when profit is zero,

40x - 300,000 = 0

40x = 300,000

x = 7,500

Hence, the break-even point is 7500.

Therefore,  the functions that represents the​ total-profit function would be p(x) = 40x - 300,000. so the correct option is A.

Learn more about function here:

https://brainly.com/question/2253924

#SPJ2

Answer:

60%

Step-by-step explanation:

[tex]percentage = \frac{24}{40} \times 100\% \\ = 60\%[/tex]

[tex]\Huge{\textbf{\textsf{{\purple{Ans}}{\pink{wer}}{\color{pink}{:}}}}} \\ [/tex]

[tex]percentage = \frac{24}{40} \times 100\% \\ = 60\%[/tex]

so answer is 60%

Answer:

[tex]\frac{1}{3}[/tex]

Step-by-step explanation:

2 = 2 × 1

6 = 2 × 3

GCF = 2

[tex]\frac{2 /2 }{6/2} =\frac{1}{3}[/tex]

Hi there!  

»»————-　★　————-««

I believe your answer is:  

[tex]\boxed{\frac{1}{3}}[/tex]

»»————-　★　————-««  

Here’s why:  

⸻⸻⸻⸻

[tex]\boxed{\text{Simplify:}}\\\\\frac{2}{6}\\\\\boxed{\text{Finding the Factors:}}\\\\2: 2\\6 : 2,3\\\\\boxed{\text{The GCF would be 2.}}\\\\\frac{2}{6} =\frac{2/2}{6/2}=\boxed{\frac{1}{3}}[/tex]

⸻⸻⸻⸻

»»————-　★　————-««  

Hope this helps you. I apologize if it’s incorrect.  

Answer:

84 cm^2

Step-by-step explanation:

The area of a triangle is

A = 1/2 bh where b is the length of the base and h is the height

A = 1/2 ( 5+9) * 12

A = 1/2 (14) * 12

A =84

Answer:

b open down and have a maximum

Step-by-step explanation:

A negative value for a will make the quadratic function open down

A downward facing parabola will have a maximum

Answer:

OK

Step-by-step explanation:

The first screenshot is for #7 and the second screenshot is for #8

Answer:

Option 3 (C)

Step-by-step explanation:

It is the only one that changes the same amount every time ( times 2 )

Answer:

16.2 cm

Step-by-step explanation:

use the pythagoran theorem

a² + b² = c²

15² + 6² = c²

225 + 36 = c²

261 = c²

Take the square root of both sides

16.1554944214 = c

Rounded

16.2 cm

Answer:

x = 16

Step-by-step explanation:

4x - 2 = 3x + 14

4x - 2 + 2 = 3x + 14 + 2

4x = 3x + 16

4x - 3x = 3x - 3x + 16

x = 16

Step-by-step explanation:

The sides with the variables are the same length, so make them equal.

x+2=2x-3

Get x alone on one side.

5=3x

Simplify.

5/3 = x

Answer:

5

Step-by-step explanation:

x+2 = 2x-3

+3 +3

x+5 = 2x

-x -x

x=5

Hope this helps! :)

Answer:

It is a sequence topic.

The general term of the sequence is 25+3(n-1) where n is the number of the term (here it is the row no.)

So the 20th term is the term with n=20. Substitute n=20 into the above general term, we will get 25+3(20-1) .

Please go on by yourself to work out the answer.

Answer:

136 mm²

Step-by-step explanation:

[tex]A=a^{2} +2a\sqrt{\frac{a^{2} }{4} } +h^{2}[/tex]

[tex]A=6^{2} +2(6)\sqrt{\frac{6^{2} }{4} } +8^{2}[/tex]

[tex]A=36 +12\sqrt{\frac{36 }{4} } +64[/tex]

[tex]A=36 +12\sqrt{9 } +64[/tex]

[tex]A=36 +12(3)+64[/tex]

[tex]A=36 +36+64[/tex]

A = 136

Answer:

5328.78

Step-by-step explanation:

formula:

[tex]P(1+\frac{i}{n})^{n*t}\\2600(1+\frac{.08}{12})^{12*9}\\\\2600(1.006667)^{108}=5328.77861305[/tex]

this rounds to 5328.78

Answer:

(40,2700)

Step-by-step explanation:

Given

[tex]D(p)=3500-20p[/tex]

[tex]S(p)=2500+5p[/tex]

Required

The equilibrium point

To do this, we have:

[tex]D(p) = S(p)[/tex]

So, we have:

[tex]2500+5p = 3500-20p[/tex]

Collect like terms

[tex]20p+5p = 3500-2500[/tex]

[tex]25p = 1000[/tex]

Divide both sides by 25

[tex]p = 40[/tex]

Substitute [tex]p = 40[/tex] in [tex]D(p)=3500-20p[/tex]

[tex]D(40) = 3500 - 20 * 40[/tex]

[tex]D(40) = 2700[/tex]

Hence, the coordinates of the equilibrium is: (40,2700)

9514 1404 393

Answer:

  x ≈ 13.7

Step-by-step explanation:

The relevant trig relation is ...

  Tan = Opposite/Adjacent

  tan(58°) = 22/x

  x = 22/tan(58°) ≈ 13.747

The value of x is about 13.7 units.

Answer:

D. V=314.2cm³

Step-by-step explanation:

The volume of the cone is:

V=pi×r²×h/3=pi×5²×12/3=100×pi=314.2cm³

Answer: D) 314.2 [tex]cm^3[/tex]

Step-by-step explanation:

The formula for finding the volume of a right cone is [tex]V=\pi r^2\frac{h}{3}[/tex]

r is the radius and h is the height/altitude.

We can sub these values in and solve

[tex]V=\pi (5^2)(\frac{12}{3} )\\V=\pi (25)(4)\\V=100\pi[/tex]

Let's sub in 3.14 for [tex]\pi[/tex] since that is a close estimate

[tex]V=(100)(3.14)\\V=314[/tex]

The volume is about 314.

Our closest answer to that is D so that is the correct choice.

Answer:

Step-by-step explanation:

From the given information, it is likely that the random variable(X) have the values below:

Let head be H

Let tail be T

So;

X(HH) = 2;

X(HT) = 1;

X(TH) = 1;

X(TT) = 0

The distribution can now be computed as:

[tex]p(X= TT) = \dfrac{1}{4}[/tex]

[tex]p(X=TH) = \dfrac{1}{4}[/tex]

[tex]p(X=HT) = \dfrac{1}{4}[/tex]

[tex]p(X=HH)= \dfrac{1}{4}[/tex]

Now, the expected value that is equivalent to the number of heads when the coin is flipped twice is:

[tex]E(X) = p(TT)*X(TT)+p(TH)*X(TH)+p(HT)*X(HT)+p(HH)*X(HH)[/tex]

[tex]E(X) = \dfrac{1}{4}\times 0 + \dfrac{1}{4}\times 1 + \dfrac{1}{4}\times 1 + \dfrac{1}{4}\times 2[/tex]

[tex]E(X) = 0 + \dfrac{1}{4}+ \dfrac{1}{4} + \dfrac{1}{2}[/tex]

[tex]E(X) =\dfrac{1+1+2}{4}[/tex]

[tex]E(X) =\dfrac{4}{4}[/tex]

E(X) = 1

[tex]E(X^2) = p(TT)*X(TT)^2+p(TH)*X(TH)^2+p(HT)*X(HT)^2+p(HH)*X(HH)^2[/tex]

[tex]E(X^2) = \dfrac{1}{4}\times 0^2+ \dfrac{1}{4}\times 1^2 + \dfrac{1}{4}\times 1^2 + \dfrac{1}{4}\times 2^2[/tex]

[tex]E(X^2) = 0 + \dfrac{1}{4}+ \dfrac{1}{4} + \dfrac{4}{4}[/tex]

[tex]E(X^2) =\dfrac{1+1+4}{4}[/tex]

[tex]E(X^2) =\dfrac{6}{4}[/tex]

[tex]E(X^2) =1.5[/tex]

Finally; To compute E²[X]

E²[X] = E[X]²

E²[X] = 1²

E²[X] = 1

Answer: they are not equivalent be 3(6x+1) is 18x+3 and 21x stays the same so there for they are not equivalent to each other

Step-by-step explanation:

Answer:

A ≈ 346.36

Step-by-step explanation:

To find the answer, you must use the formula, A=πr²

Since only the diameter was provided, you need to divide it by 2 to find the radius. 21 divided by 2 equals 10.5, so that will be your radius.

Another formula that can be used while using only the diameter would be A= 1/4 π d²

answer is

(Y)=-23,-14, -5,4,13

hope this will help you

Answer:

consist of either a single capital letter or a capital letter and a small letter.

Step-by-step explanation:

A chemical reaction can be defined as a reaction in which two or more atoms of a chemical element react to form a chemical compound.

In Chemistry, a chemical element can be defined as any pure substance that is typically made up of only atoms and cannot be broken down into simpler substances through chemical processes. Thus, the atomic number (the number of protons in the nuclei of an atom) of a particular chemical element distinguishes from other chemical elements.

Generally, all chemical elements are denoted or represented by a symbol, which may either be single capital letter or a capital letter and a small letter.

This ultimately implies that, the symbols for elements with accepted names consist of either a single capital letter or a capital letter and a small letter. For example, the symbol for sodium is Na, copper is Cu, carbon is C, oxygen is O, iron is Fe, nitrogen is N, magnesium is Mg, potassium is K, argon is Ag, hydrogen is H, helium is He, phosphorus is P, etc.

Answer:

c. -x + 3x + 7  = 2x+7

Step-by-step explanation:

f(x) = 3x +1 and g(x) = x - 6

f-g = 3x +1 - ( x - 6)

Distribute the minus sign

     = 3x+1 - x+6

     = 2x +7

Answer:

it should be 314.16, so I would choose 314