Answer:
The calculated value of z = - 0.197 falls in the critical region therefore we reject the null hypothesis and conclude that at the 5% significance level there is significant difference in population proportions of households that decorate their houses with lights for the holidays
Step-by-step explanation:
We formulate the null and alternative hypotheses as
H0: p1= p2 there is no difference in population proportions of households that decorate their houses with lights for the holidays
against Ha : p1≠ p2 (claim) ( two sided)
The significance level is set at ∝= 0.05
The critical value for two tailed test at alpha=0.05 is ± 1.96
or Z∝= 0.05/2= ± 1.96
The test statistic is
Z = p1-p2/√pq(1/n1 +1/n2)
p1= proportions of households decorating in city 1 = 45/60=0.75
p2= proportions of households decorating in city 2 = 40/50= 0.8
p = the common proportion on the assumption that the two proportion are same.
p = [tex]\frac{n_1p_1 +n_2p_2}{n_1+n_2}[/tex]
Calculating
p =60 (0.75) + 50 (0.8) / 110
p= 45+ 40/110= 85/110 = 0.772
so q = 1-p= 1- 0.772= 0.227
Putting the values in the test statistic and calculating
z= 0.75- 0.8/ √0.772*0.227( 1/60 + 1/50)
z= -0.05/√ 0.175244 ( 110/300)
z= -0.05/0.25348
z= -0.197
The calculated value of z = - 0.197 falls in the critical region therefore we reject the null hypothesis and conclude that at the 5% significance level there is significant difference in population proportions of households that decorate their houses with lights for the holidays
Extensive experience with fans of a certain type used in diesel engines has suggested that the exponential distribution provides a good model for time until failure. Suppose the mean time until failure is 23,100 hours.
(a) What is the probability that a randomly selected fan will last at least 20,000 hours?
What is the probability that a randomly selected fan will last at most 30,000 hours?
What is the probability that a randomly selected fan will last between 20,000 hours and 30,000 hours?
(b) What is the probability that the lifetime of a fan exceeds the mean value by more than 2 standard deviations?
What is the probability that the lifetime of a fan exceeds the mean value by more than 3 standard deviations?
Answer:
0.4207149;0.7271136; 0.3063987; 0.04979 ; 0.01832
Step-by-step explanation:
For an exponential distribution:
IF Mean time until failure = 23100
λ = 1/ 23100 = 0.0000432900
What is the probability that a randomly selected fan will last at least 20,000 hours
x ≥ 20000
P(X ≥ 20000) = 1 - P(X ≤ 20000)
1 - P(X ≤ 20000) = [1 - (1 - e^(-λx))]
1 - P(X ≤ 20000) = [1 - (1 - e^(-0.0000432900*20000)
1 - P(X ≤ 20000) = [1 - (1 - 0.4207148)]
1 - P(X ≤ 20000) = 1 - 0.5792851
1 - P(X ≤ 20000) = 0.4207149
11) What is the probability that a randomly selected fan will last at most 30,000 hours?
x ≤ 30000
P(X ≤ 30000) = 1 - e^(-λx)
P(X ≤ 20000) = 1 - e^(-0.0000432900*30000)
= 1 - e^(−1.2987)
= 1 - 0.2728863
= 0.7271136
111) What is the probability that a randomly selected fan will last between 20,000 hours and 30,000 hours?
0.7271136 - 0.4207149 = 0.3063987
B) What is the probability that the lifetime of a fan exceeds the mean value by more than 2 standard deviations?
More than two standard deviation
X = 23100 + 2(23100) = 23100 + 46200 = 69300
Using the online exponential probability calculator :
P(X > 69300) = 0.04979
C) What is the probability that the lifetime of a fan exceeds the mean value by more than 3 standard deviations?
X = 23100 + 3(23100) = 23100 + 69300 = 92400
P(X > 92400) = 0.01832
How long will it take for a lump-sum investment to double in value at an interest rate of 1.5% per month, compounded continuously
Answer:
It will take 47 months ( 3 years and 11 months)
Step-by-step explanation:
We use the compound interest formula here.
Mathematically;
A = P( 1 + r)^t
Where A is the amount which is 2 times the principal here, so we can call it 2P
P is the lump-sum invested
r is the monthly interest rate given as 1.5% = 1.5/100 = 0.015
t = time , which we want to calculate
Substituting these values, we have;
2P = P(1 + 0.015)^t
divide both sides by P
2 = 1.015^t
Take the log of both sides;
log 2 = log (1.015)^t
log 2 = t log 1.015
t = log2/log1.015
t = 46.55
which is approximately 47 months
Relating a Polynomial Identity to Pythagorean Triples
In this activity you'll relate polynomial identities with Pythagorean triples. Answer the following questions
based on this triangle with side lengths x^2 – 1, 2x, and x^2 + 1.
Answer:
Step-by-step explanation:
Hello, please consider the following.
For x > 1, we can apply Pythagoras theorem as below.
[tex]\text{Let's estimate this sum of two squares.} \\\\(2x)^2+(x^2-1)^2=4x^2+x^4-2x^2+1=x^4+2x^2+1\\\\\text{Let's estimate this square, now.} \\\\(x^2+1)^2=x^4+2x^2+1\\\\\text{The two expressions are equal, meaning.} \\\\(2x)^2+(x^2-1)^2=(x^2+1)^2\\\\\text{Using Pythagoras' theorem, we can say that this is a right triangle.}[/tex]
Thank you
A number to be multiplied is called a?
Answer:
The number to be multiplied is the "multiplicand"
Step-by-step explanation:
a base when it is written in exponential notation
Which is an example of a situation that is in equilibrium?
A. The amount of air in a room increases quickly when the door is
opened.
B. The amount of money in a bank account never changes
C. The amount of water in a cup decreases as it evaporates
D. A flower slowly grows taller
Answer:B the amount of money in a bank account never changes.
Step-by-step explanation:
Answer:
B. The amount of money in a bank account never changes.
Step-by-step explanation:
Equilibrium is achieved when the state of a reversible reaction of opposing forces cancel each other out. While in a state of equilibrium, the competing influences are balanced out. Imagine a cup with a hole in it being filled with water from a tap. The level of water in this cup would stay the same if the rate at which the water that flows inside is the same as the water that flows outside. Option B will be the correct answer because the amount of money going into the account is at the same rate of money coming out of the account.
Show that the set of functions from the positive integers to the set {0, 1, 2, 3, 4, 5, 6, 7, 8, 9} is uncountable. [Hint: First set up a one-to-one correspondence between the set of real numbers between 0 and 1 and a subset of these functions. Do this by associating to the real number 0.d1d2 . . . dn . . . the function f with f(n).
Answer:
since the set of functions expressed are uncountable and they are a subset of real numbers starting from N therefore the set {0,1,2,3,4,5,6,7,8,9} is uncountable as well as its off functions
Step-by-step explanation:
set = {0,1,2,3,4,5,6,7,8,9}
setting up a one-to-one correspondence between the set of real numbers between 0 and 1
The function : F(n)= {0,1} is equivalent to the subset (sf) of (n) , this condition is met if n belongs to the subset (sf) when f(n) = 1
hence The power set of (n) is uncountable and is equivalent to the set of real numbers given
since the set of functions expressed are uncountable and they are a subset of real numbers starting from N therefore the set {0,1,2,3,4,5,6,7,8,9} is uncountable as well as its offfunctions
Find x in each triangle. PLZ ANSWER FAST!!!!!!!!!!!
Find the area of the shape shown below.
2
2
nd
2
Need help Plz hurry and answer!!!
Answer:
=6 units squared
Step-by-step explanation:
area=1/2h(a+b)
=1/2×2(4+2)
=6
If the area of the square is A(s) = s², find the formula for the area as a function of time, and then determine A(s(3)).
A(t) = 100t^2 + 500t + 625
3,025 square pixels
Answer:
A(t) equals 100t²+ 500t + 625.
The area of the square image after 3 seconds is 3,025 square pixels.
Can someone please help me with this question?
Answer:
B
Step-by-step explanation:
11q + 5 ≤ 49
Subtract 5 from each side
11q + 5-5 ≤ 49-5
11q ≤44
Divide each side by 11
q ≤44/11
q≤4
There is a close circle at 4 because of the equals sign and the lines goes to the left
Answer:
B
Step 1:
To solve this, we need to isolate the variable q. To do so, we will subtract 5 from both sides of the inequality.
[tex]11q+5(-5)\leq 49(-5)\\11q\leq 44[/tex]
Step 2:
We divide both sides by 11 to get our q.
[tex]\frac{11q}{11}\leq \frac{44}{11} \\q\leq 4[/tex]
q ≤ 4
Step 3:
To find the correct graph, we need to know that a close circle means a ≤ or ≥ and an open one means a < or >. Here, we are using a ≤ so C and D are not our answers. Also remember that if the "arrow" is pointing left (<), then the arrow on the graph should be facing the left side. If the arrow is facing the right side, then that means we are using > or ≥. Here, we are using ≤ (left), so that means the arrow on the graph should be on a 4, facing left, with a closed circle.
Our answer is B.
Solve the equation 3(2x + 2) = 3x − 15.
Hi there! :)
Answer:
x = -7.
Step-by-step explanation:
Starting with:
3(2x + 2) = 3x - 15
Begin by distributing '3' with the terms inside of the parenthesis:
3(2x) + 3(2) = 3x - 15
Simplify:
6x + 6 = 3x - 15
Isolate the variable by subtracting '3x' from both sides:
6x - 3x + 6 = 3x - 3x - 15
3x + 6 = -15
Subtract 6 from both sides:
3x + 6 - 6 = -15 - 6
3x = -21
Divide both sides by 3:
3x/3 = -21/3
x = -7.
Answer:
x = -7
Step-by-step explanation:
3(2x+2) = 3x - 15
First, we should simplify on the left side.
6x + 6 = 3x - 15 ; Now we subtract six from both sides.
-6 -6
6x = 3x - 21 ; next we just subtract 3x from both sides.
-3x -3x
3x = -21
Finally, we divide 3 from both sides to separate the three from the x.
x = -7
Hope this helps!! <3 :)
Find the total surface area of the farm silo in a farmer's field. Use π = 3.14. pls help asap uwu
Answer:
A) 1236 units²
Step-by-step explanation:
Cylinder = 2[tex]\pi[/tex]h+2[tex]\pi[/tex]r²
2(3.14)(7.5)(15)+2(3.14)(7.5x7.5)
706.5+353.25=1059.75
1/2 Sphere = 1/2(4)[tex]\pi[/tex]r²
2(3.14)(7.5)(7.5)
353.25
TOTAL: 1059.75+353.25=1413
HOWEVER...you need to subtract the top of the cylinder ([tex]\pi[/tex]r²) 176.625
1413-176.625=1236.375
So the answer would be A. (Silo’s do have a bottom, or else the answer would be D)
Answer:
1,236 units²
Step-by-step explanation:
I got it correct on founders edtell and screenshot below as proof
The driveway needs to be resurfaced. what is the BEST estimate of the area of the driveway?
Answer:
125π ft²
Step-by-step explanation:
1/4π(30)² - 1/4π(20)² = 125π
Which graph has an amplitude of 1/2?
Answer:
Step-by-step explanation:
The only graph shown in the question doesn't have amplitude 1/2. look for a graph of a periodic wave function that has maximum y-value 1/2 (0.5) and minimum y-value 1/2 (0.5), or if it is not oscillating around the x-axis, verifies that the distance between minimum y-value and maximum y-value is "1" (one). This is because the amplitude is half of the peak-to-peak distance.
Look at the attached image as example.
Answer:
Answer is B
Step-by-step explanation:
Did it on Edge
This is the ASVAB question If 500 people are at a concert and 70% are adults. How many children are there?
Answer:
150
Step-by-step explanation:
70% of 500 people are adults and the remainder are children.
30% of 500 are children30*500/100= 150There are 150 children
Find the length of GV¯¯¯¯¯¯¯¯ A. 43.92 B. 33.1 C. 41.45 D. 68.87
Answer:
The answer is option AStep-by-step explanation:
Since the figure above is a right angled triangle we can use trigonometric ratios to find GV
To find GV we use cosine
cos∅ = adjacent / hypotenuse
From the question
GV is the adjacent
GC is the hypotenuse
So we have
[tex] \cos(37) = \frac{GV}{GC} [/tex]GC = 55°
GV[tex] \cos(37) = \frac{GV}{55} [/tex]GV = 55 cos 37
GV = 43.92495
We have the final answer as
GV = 43.92Hope this helps you
A researcher is interested in determining whether typists are most productive in the morning, at midday, in the evening, or late at night. To answer this question, the researcher recruits 20 participants and assigns 5 participants to be measured at each time of day. To evaluate productivity, the researcher measures words typed per minute at each time of day.
Morning Midday Evening Night
99 42 80 82
80 32 83 78
99 45 94 79
98 49 70 97
79 38 79 96
Mean 91 41.2 81.2 86.4
SStotal = 9094.95
What are the degrees of freedom for the numerator of the F-ratio?
a. 2
b. 3
c. 16
d. 19
Answer:
d. 19
Step-by-step explanation:
Degrees of freedom is the number is the number of value which is used in the final calculation. It calculate as n-1, where n is the sample size. The degrees of freedom for the given scenario is 19. The sample size is 20 so the degrees of freedom is 1 less which will be 19.
The price of a technology stock was $ 9.56 yesterday. Today, the price rose to $ 9.69 . Find the percentage increase. Round your answer to the nearest tenth of a percent.
Answer and Step-by-Step explanation:
% increase = 100 x [(new price) - (original price)] / (original price)] = 100 (9.67 - 9.56) / 9.56
% increase ≅ 1.2% (to the nearest tenth)
If sin∠M = cos∠N and m∠N = 30°, what is the measure of ∠M?
Step-by-step explanation:
sin∠M = cos∠N
sin∠M = cos(30°)
sin∠M = √3 / 2
m∠M = 60° or 120°
If ∠M is acute, m∠M = 60°.
Answer: The measure of ∠M is 60°
Step-by-step explanation:
The complement of 30° is 60°
sin∠M =cos∠N
sin∠60°=cos∠30°
the measure of ∠M is 60°
Even though the population standard deviation is unknown, an investigator uses z rather than the more appropriate t to test a hypothesis at the .01 level of significance. In this situation the true level of significance of this test is
Answer:
The true true level of significance of this test is more than 0.01.
Step-by-step explanation:
No standard deviation and we are told that the investigator still used z rather than the more appropriate t - distribution.
This method of using the z-distribution when standard deviation is unknown will definitely result in a smaller critical value and this in turn simply means that the p-value will be smaller than what it should really be.
Thus, it means the critical value is getting closer to the mean value than the way it should be.
Therefore, means that for a given significance of 0.01 and using the z-distribution under this no standard deviation situation, the true true level of significance of this test is more than 0.01.
The number of values of xx in the interval [0,5π][0,5π] satisfying the equation 3sin2x−7sinx+2=03sin2x-7sinx+2=0 is/are
Answer:
6
Step-by-step explanation:
Given, 3sin2x−7sinx+2=03sin2x-7sinx+2=0
⇒(3sinx−1)(sinx−2)=0⇒3sinx-1sinx-2=0
⇒sinx=13 or 2⇒sinx=13 or 2
⇒sinx=13 [∵sinx≠2]⇒sinx=13 [∵sinx≠2]
Let sinα=13,0<α<π2,sinα=13,0<α<π2, then sinx=sinαsinx=sinα
now x=nπ+(−1)nα(n∈I)x=nπ+(−1)nα(n∈I)
⇒x=α,π−α,2π+α,3π−α,4π+α,5π−α⇒x=α,π−α,2π+α,3π−α,4π+α,5π−α Are the solution in [0,5π][0,5π]
Hence, required number of solutions are 6
marc mixes blue and yelow paint to ,ake green he has 14 cans blue 20 cans of yellow . he wants green color so one day 1 he mixes 4 blue 6 yellow day 2 he mixes 6 can blue 9 yellowwhats the highest number of cans each color marc can mix to mzke the same shade of green on day 3
Answer:
2 c an of blue and 5 can of yellow
Step-by-step explanation:
In this problem, we explore the effect on the mean, median, and mode of adding the same number to each data value. Consider the data set 6, 6, 7, 10, 14.
Answer
The mean is 8.6
The median is 7
And the mode is 6
The one-sample z test is: a. a hypothesis test b. used to test hypotheses c. concerning a single population with a known variance d. concerning at least one population e. concerning the variance in a population d. all of the above
Answer:
d. all of the above
Step-by-step explanation:
A one sample z test measures whether the mean of a population is greater, less or equal to a specific value. It is called one sampl z test since the standard normal distribution is used in calculation of critical values. It makes use of the null hypothesis and alternative hypothesis in determining if the mean is greater than or equal or less than the reference value. Variance and standard deviation is assumed to be known and at least one population is used
A collector as a set of 224 coins. Some are valued at 20 cents and others at 25 cents. If the collector has 74 25-cent coins, then what is the total value of the collection
Answer:
48.50 dollars.
Step-by-step explanation:
The collector has a total of 224 coins but 74 of them are 25 cents coins. So, in order to find the number of 20-cent coins we're going to subtract the number of 25-cent coins from the total.
Number of 20-cent coins = 224 - 74 = 150.
Thus, the collector has 150 20-cent coins and 74 25-cent coins for a total of 224 coins.
Now, to know the total value of the collection we need to multiply the value of the coins by the number of coins there are of this value (we are going to do it with the 20-cent and the 25-cent coins) and then sum up our results.
Total value = 74(25) + 150 (20) = 1850 + 3000 = 4850 cents.
So the total value is 4850 cents, we know that each dollar has 100 cents so, to express this number in dollars we are going to divide it by 100 and thus we have that the total value of the collection is 48.50 dollars.
identify the decimals labeled with the letters A, B, and C on the scale below. Letter A represents the decimal Letter B represents the decimal Letter C represents the decimal
[tex]10[/tex] divisions between $20$ and $20.1$ so each division is $\frac{20.1-20.0}{10}=0.01$
A is 2nd division from $20.0$, so, A is $20.0+2\times 0.01=20.02$
similarly, C is one division behind $20.0$ so it is 19.99
and B is $20.14$
A certain family has a husband, wife, son, and daughter. All together they are 68 years old. The husband is 3 years older than the wife, and the son is 3 years older than the daughter. Four years ago, all together the family was 54 years old. How old is the husband now?
Answer:
32 years old
Step-by-step explanation:
The husband is 32 years old as the wife is 3 years younger than the husband. The son is 3 years older than the daughter. Their family altogether total age today is 68 years while 4 years ago their age total was 54 years. The difference is 14 years. If we divide the difference into 4 then the age can not be whole number which means daughter is born after 2 years. She is now 2 years older. Son is 3 years older than the daughter which means he is 5 years old. The husband then must be 32 years old and wife is 3 years younger which means she is 29 years old now.
32 + 29 + 5 + 2 = 68 years.
Find the union and interesection of each of the following A={3,6,9,12}, B ={6,8,9}
Answer:
Hello,
The answer would be,
A union B = {3,6,9,12}
and A intersection B= {6,9}
Answer:
[tex]\huge\boxed{ A\ union \ B = \{3,6,8,9,12\}}[/tex]
[tex]\huge\boxed{A\ intersection \ B = \{6,9\}}[/tex]
Step-by-step explanation:
A = {3,6,9,12}
B = {6,8,9}
A∪B = {3,6,9,12} ∪ { 6,8,9} [Union means all of the elements should be included in the set of A∪B]
=> A∪B = {3,6,8,9,12}
Now,
A∩B = {3,6,9,12} ∩ {6,8,9} [Intersection means common elements of the set]
=> A∩B = {6,9}
Is {(4,2),(4,-2),(9,3),(9,-3)} a function
Answer:
no
Step-by-step explanation:
If any x-value is repeated, the relation is not a function. Both x=4 and x=9 are repeated values, so this relation is not a function.
What number should both sides of the following equation be multiplied by to solve for g? g divided by 2 = 4
Answer: Multiply both sides by 2.
Step-by-step explanation:
g divided by 2 is equal to 4 .
We could represent that with the equation :
[tex]\frac{g}{2} = 4[/tex] To solve for g in this case multiply both sides by 2.
[tex]\frac{g}{2} * 2 = 4(2)[/tex] 2 cancels out on the left side so we will be left with g. On the right side will be left with 8 after multiplying.
g = 8
