Answer:
[tex]n=(\frac{1.440(2.3)}{0.12})^2 =761.76 \approx 762[/tex]
So the answer for this case would be n=762 rounded up to the nearest integer
Step-by-step explanation:
Information given
[tex]\bar X = 17[/tex] represent the mean
[tex]\mu[/tex] population mean (variable of interest)
[tex]\sigma= \sqrt{5.29}= 2.3[/tex] represent the standard deviation
Solution to the problem
The margin of error is given by this formula:
[tex] ME=z_{\alpha/2}\frac{s}{\sqrt{n}}[/tex] (a)
And on this case we have that ME =0.12 and we are interested in order to find the value of n, if we solve n from equation (a) we got:
[tex]n=(\frac{z_{\alpha/2} \sigma}{ME})^2[/tex] (b)
The confidence level is 85%, the significance level would be [tex] \alpha=1-0.85 = 0.15[/tex] and [tex]\alpha/2 =0.075[/tex] the critical value for this case would be [tex]z_{\alpha/2}=1.440[/tex], replacing into formula (b) we got:
[tex]n=(\frac{1.440(2.3)}{0.12})^2 =761.76 \approx 762[/tex]
So the answer for this case would be n=762 rounded up to the nearest integer
An automobile manufacturer has given its van a 31.3 miles/gallon (MPG) rating. An independent testing firm has been contracted to test the actual MPG for this van since it is believed that the van has an incorrect manufacturer's MPG rating. After testing 140 vans, they found a mean MPG of 31.1. Assume the population standard deviation is known to be 1.3. A level of significance of 0.02 will be used. State the null and alternative hypotheses.
Answer:
[tex]z=\frac{31.1-31.3}{\frac{1.3}{\sqrt{140}}}=-1.82[/tex]
The p value for this case would be given by:
[tex]p_v =2*P(z<-1.82)=0.0688[/tex]
For this case since the p value is higher than the significance level we have enough evidence to FAIL to reject the null hypothesis and we can conclude that the true mean is not significantly different from 31.3 MPG
Step-by-step explanation:
Information given
[tex]\bar X=31.1[/tex] represent the sample mean
[tex]\sigma=1.3[/tex] represent the population standard deviation
[tex]n=140[/tex] sample size
[tex]\mu_o =31.3[/tex] represent the value that we want to test
[tex]\alpha=0.02[/tex] represent the significance level for the hypothesis test.
z would represent the statistic
[tex]p_v[/tex] represent the p value
Hypothesis to test
We want to test if the true mean is equal to 31.3 MPG, the system of hypothesis would be:
Null hypothesis:[tex]\mu =31.3[/tex]
Alternative hypothesis:[tex]\mu \neq 31.3[/tex]
Since we know the population deviation, the statistic is given by
[tex]z=\frac{\bar X-\mu_o}{\frac{\sigma}{\sqrt{n}}}[/tex] (1)
Replacing we got:
[tex]z=\frac{31.1-31.3}{\frac{1.3}{\sqrt{140}}}=-1.82[/tex]
The p value for this case would be given by:
[tex]p_v =2*P(z<-1.82)=0.0688[/tex]
For this case since the p value is higher than the significance level we have enough evidence to FAIL to reject the null hypothesis and we can conclude that the true mean is not significantly different from 31.3 MPG
The average age of all students at a certain college is 22 years and the standard deviation is 2 years. What is the probability that the average age of a randomly selected sample of 100 students will be less than 21.8 years
Answer:
The probability that the average age of a randomly selected sample of 100 students will be less than 21.8 years is 0.159
Step-by-step explanation:
According to the given data we have the following:
mean = μ= 22
standard deviation = σ = 2
n = 100
μx = 22
σx=σ/√n=2/√100=0.2
Therefore, P( x < 21.8)=P(x-μx)/σx<(21.8-22)/0.2
=P(z<-1)
= 0.159
The probability that the average age of a randomly selected sample of 100 students will be less than 21.8 years is 0.159
A sanitation supervisor is interested in testing to see if the mean amount of garbage per bin is different from 50. In a random sample of 36 bins, the sample mean amount was 48.99 pounds and the sample standard deviation was 3.7 pounds. Conduct the appropriate hypothesis test using a 0.01 level of significance.
a) What is the test statistic? Give your answer to four decimal places.
b) What is the P-value for the test? Give your answer to four decimal places.
Answer:
Step-by-step explanation:
Claim: if the mean amount of garbage per bin is different from 50.
Null hypothesis: u=50
Alternative hypothesis : u =/ 50
Using the z score formular for a one sample z test - z = (x - u ) / (sd/√n)
Where x = 48.99, u = 50 sd =3.7 and n = 36
z = 48.99 - 50 / (3.7/√36)
z = -1.01 / (3.7/6)
z = -1.01/0.6167
z = -1.6377
To find the p value at a 0.01 level of significant from the -1.6377 z score for a two tailed test the p value using the p value calculator is 0.1016. The result is not significant at 0.01 level of significant thus we will fail to reject the null and conclude that the mean amount of garbage per bin is 50.
What are the solutions to the system of equations graphed below? Select all
that apply
A. (-6,8)
B. (0,2)
C. (2,0)
D. (-5,0)
E. (0,-10)
Answer:
c and d
Step-by-step explanation:
the x intercepts are the solutions
Answer:
(0,2) and (-5,0)
Step-by-step explanation:
the point where the two graph lines meet would be the answer.
A television network, Network A, is scheduling its fall lineup of shows. For the Tuesday night 8 p.m. slot, Network A has selected its top show. If its rival network, Network B, schedules its top show during the same time slot, Network A estimates that it will get 1.1 million viewers. However, if Network B schedules a different show during that time slot, Network A estimates that it will get 1.9 million viewers. Network A believes that the probability that Network B will air their top show is 0.7 and the probability that Network B will air another show is 0.3. Determine the expected number of viewers for Network A's top show.
Answer:
1,280,000 (1.28 million.)
Step-by-step explanation:
If Network B schedules its top show (with a probability of 0.7), Network A will get 1.1 million viewers.
If Network B schedules a different show during that time slot, (with a probability of 0.3), Network A will get 1.9 million viewers.
Therefore, the probability distribution table of number of viewers of Network A is:
[tex]\left|\begin{array}{c|c|c}$Number of Viewers, x&1.1$ million&$1.7 million\\P(x)&0.7&0.3\end{array}\right|[/tex]
Therefore, the expected number of viewers for Network A's top show
= (1100000 X 0.7) + (1700000 X 0.3)
=1,280,000
The expected number of viewers for Network A's top show is 1.28 million.
A sample of 1300 computer chips revealed that 58% of the chips do not fail in the first 1000 hours of their use. The company's promotional literature states that 61% of the chips do not fail in the first 1000 hours of their use. The quality control manager wants to test the claim that the actual percentage that do not fail is different from the stated percentage. Find the value of the test statistic. Round your answer to two decimal places.
Answer:
There is enough evidence to support the claim that that the actual percentage that do not fail is different from the stated percentage (61%).
Test statistic z = -2.19.
P-value = 0.03.
Step-by-step explanation:
This is a hypothesis test for a proportion.
The claim is that that the actual percentage that do not fail is different from the stated percentage (61%).
Then, the null and alternative hypothesis are:
[tex]H_0: \pi=0.61\\\\H_a:\pi\neq 0.61[/tex]
The significance level is assumed to be 0.05.
The sample has a size n=1300.
The sample proportion is p=0.58.
The standard error of the proportion is:
[tex]\sigma_p=\sqrt{\dfrac{\pi(1-\pi)}{n}}=\sqrt{\dfrac{0.61*0.39}{1300}}\\\\\\ \sigma_p=\sqrt{0.000183}=0.014[/tex]
Then, we can calculate the z-statistic as:
[tex]z=\dfrac{p-\pi+0.5/n}{\sigma_p}=\dfrac{0.58-0.61+0.5/1300}{0.014}=\dfrac{-0.03}{0.014}=-2.189[/tex]
This test is a two-tailed test, so the P-value for this test is calculated as:
[tex]\text{P-value}=2\cdot P(z<-2.189)=0.03[/tex]
As the P-value (0.03) is smaller than the significance level (0.05), the effect is significant.
The null hypothesis is rejected.
There is enough evidence to support the claim that that the actual percentage that do not fail is different from the stated percentage (61%).
How many edges and vertices does a prism with 100 sided end faced have ? Please answer as quickly as possible ≈[infinity]
Answer:
We have 300 edges and 200 vertices
Step-by-step explanation:
A prism is basically a 2D shape which extends into three dimensions. Thus, it has two end faces, and one face for each side on the original shape.
In addition to the two 100-sided polygons at top and bottom, the prism will also have 100 rectangular faces.
We will solve this by Euler’s formula which ks:
V - E + F = 2
where;
V is the number of vertices (corners),
E is the number of edges
F is the number of faces (of any polyhedron).
Number of vertices is 100 surrounding the top while it's 100 at the bottom. So total V = 100 + 100 = 200 .
The number of edges is 100 at the top, and 100 at the bottom. Also an additional 100 separating the hundred vertical faces.
Total number of edges is;
E = 100 + 100 + 100 = 300.
Thus, we have 300 edges and 200 vertices
Question 1 of 10
2 Points
The standard form of the equation of a parabola is y = 7x2 + 14x + 4.
What is the vertex form of the equation?
A. y = 7(x + 1)2-3
B. y= 7(x + 2)2-3
c. y= 7(x + 1)2 + 3
D. y= 7(x + 2)2 + 3
SUBMIT
Answer:
A. y = 7(x + 1)²-3
Step-by-step explanation:
Parabola:
[tex]y = 7x^{2} + 14x + 4[/tex]
[tex]y = 7(x^{2} + 2x) + 4[/tex]
Putting into vertex form, remember that:
[tex](x + a)^{2} = x^{2} + 2ax + a^{2}[/tex]
In this question:
[tex]x^{2} + 2x[/tex], to put into this format:
[tex]x^{2} + 2x + 1 = (x + 1)^{2}[/tex]
We add one inside the parenthesis to do this. The parenthesis is multiplied by 7, so for the equivalent, we also have to subtract 7. Then
Vertex form:
[tex]y = 7(x^{2} + 2x + 1) + 4 - 7[/tex]
[tex]y = 7(x + 1)^{2} - 3[/tex]
So the correct answer is:
A. y = 7(x + 1)²-3
Which is the better buy?. Store A $180 at 1/3 off Or Store B $110 at 10% off (SHOW YOUR WORK)
Answer:
not 100% sure but my answer is 110
Step-by-step explanation:
It is More Affordable and is the better Buy From All the other choices.
What is the quoteint of 2/3 in 2/9
Please answer this correctly
Answer:
First box is 4This is because 2 is the stem and the leaves are 1, 2, 4, and 5
so the numbers are 21, 22, 24, and, 25
Second box is 3This is because 2 is the stem for the leaves 6 and 7
3 is the stem for the leaf 0
So the numbers are 26, 27, and 30
Hope this helped
Answer:
As you know about the stem and leaf plot
1 |7 7 7 8 => 17, 17, 17, 18
2|1 2 4 5 6 7 => 21, 22, 24, 25, 26, 27
3|0 2 5 5 6 7 7 8 9 => 30, 32, 35, 35, 36, 37, 37, 38, 39
4|1 2 => 41, 42
Now we count to complete the table:
16-20 | 4 {17, 17, 17, 18}
21-25 | 4 {21, 22, 24, 25}
26-30 | 3 {26, 27, 30}
31-35 | 3 {32, 35, 35}
36-40 | 5 {36, 37, 37, 38, 39}
41-45 | 2 {41, 42}
Hope this helps!
Suppose we want to study the weekly rate of alcohol drinking among USF undergraduate students. Which of the following would be the LEAST preferred method of randomly selecting participants?
A. Selecting a random sample of students from each residence hall
B. Selecting a random sample of students from the list of all undergraduate students from the university's registrar office
C. Selecting a random sample of students who have used the university health services in the past month
D. Selecting a random sample of students from each college
Answer:
Option D
Step-by-step explanation:
I think the least preferred method the researcher would like is to select a random sample of students from each college. This means the researcher would have to go to every college and randomly selects participants which is very exhausting. Thus, this would be the least prefer method over the others...
The mail arrival time to a department has a uniform distribution over 5 to 45 minutes. What is the probability that the mail arrival time is more than 25 minutes on a given day? Answer: (Round to 2 decimal places.)
Answer:
0.5
Step-by-step explanation:
An uniform probability is a case of probability in which each outcome is equally as likely.
For this situation, we have a lower limit of the distribution that we call a and an upper limit that we call b.
The probability that we find a value X higher than x is given by the following formula.
[tex]P(X > x) = \frac{b - x}{b-a}[/tex]
The mail arrival time to a department has a uniform distribution over 5 to 45 minutes.
This means that [tex]a = 5, b = 45[/tex].
What is the probability that the mail arrival time is more than 25 minutes on a given day?
[tex]P(X > 25) = \frac{45 - 25}{45 - 5} = 0.5[/tex]
So the probability that the mail arrival time is more than 25 minutes on a given day is 0.5.
Once a fire is reported to a fire insurance company, the company makes an initial estimate, X, of the amount it will pay to the claimant for the fire loss. When the claim is finally settled, the company pays an amount, Y, to the claimant. The comapny has determined that X and Y have the joint density functionf(x,y) = Given that the initial claim estiamted by the comapny is 2, determine the probability that the final settlement amount is between 1 and 3.
Answer:
The probability that the final settlement amount is between 1 and 3 given that the initial claim is 2 = (2/9) = 0.2222
Step-by-step explanation:
The complete question is presented in the attached image to this solution
The joint probability distribution is given as
f(x, y) = {2/[x²(x - 1)} × y^-[(2x-1)/(x-1)] for x>1 And y>1
Given that the initial claim estiamted by the comapny is 2, determine the probability that the final settlement amount is between 1 and 3.
That is, x = 2, and y ranges from 1 to 3
Inserting x = 2 into the expression, we obtain
f(y) = (1/2) × y⁻³ = (y⁻³/2)
The required probability would then be
P(1 < y ≤ 3) = ∫³₁ f(y) dy
= ∫³₁ (y⁻³/2) dy
= [y⁻²/-4]³₁
= [3⁻²/-4] - [1⁻²/-4]
= (-1/36) - (-1/4)
= (1/4) - (1/36)
= (8/36)
= (2/9) = 0.2222
Hope this Helps!!!
g A life insurance salesman sells on the average 3 life insurance policies per week. Calculate the probability that in a given week he will sell 2 or more policies but less 4 policies.
Answer:
44.80% probability that in a given week he will sell 2 or more policies but less than 4 policies.
Step-by-step explanation:
In a Poisson distribution, the probability that X represents the number of successes of a random variable is given by the following formula:
[tex]P(X = x) = \frac{e^{-\mu}*\mu^{x}}{(x)!}[/tex]
In which
x is the number of sucesses
e = 2.71828 is the Euler number
[tex]\mu[/tex] is the mean in the given interval.
A life insurance salesman sells on the average 3 life insurance policies per week.
This means that [tex]\mu = 3[/tex]
Calculate the probability that in a given week he will sell 2 or more policies but less 4 policies.
[tex]P(2 \leq X < 4) = P(X = 2) + P(X = 3)[/tex]
In which
[tex]P(X = x) = \frac{e^{-\mu}*\mu^{x}}{(x)!}[/tex]
[tex]P(X = 2) = \frac{e^{-3}*3^{2}}{(2)!} = 0.2240[/tex]
[tex]P(X = 3) = \frac{e^{-3}*3^{3}}{(3)!} = 0.2240[/tex]
[tex]P(2 \leq X < 4) = P(X = 2) + P(X = 3) = 0.2240 + 0.2240 = 0.4480[/tex]
44.80% probability that in a given week he will sell 2 or more policies but less than 4 policies.
The sum of the ages of ahsan and his mother is 61 years.The difference in their ages is 29 years.By forming a pair of simultaneous linear equations,find (i)ahsan's present age (ii)the age of ahsan's mother when ahsan is 21 years old
Answer:
a. 16 years
b. 50 years
Step-by-step explanation:
Let us assume the age of Ahsan be X
And, the age of his mother be Y
It is mentioned in the question that the sum of the both ages to be 61 years and their difference is 29 years
So now the equation is as follows
X + Y = 61 .............................. (1)
-X + Y = 29 .............................. (2)
Now solve this
We get
2Y = 90
Y = 45 = Ahsan mother age age
Now put the value of Y in any of the above equation
So X would be
X = 61 - 45
= 16 i.e ahsan age
The mother age is
= 45 years + 5 years
= 50 years
The 5 years come from
= 21 years - 16 years
= 5 years
write 2^((5)/(2)) in surd form
Answer:
[tex]\sqrt{2^5}[/tex]
Step-by-step explanation:
The applicable rule of exponents is ...
[tex]\displaystyle a^{b/c}=\sqrt[c]{a^b}[/tex]
So, ...
[tex]2^{5/2}=\boxed{\sqrt{2^5}}[/tex]
_____
This can be simplified to ...
[tex]\sqrt{32}=4\sqrt{2}[/tex]
I sell hot dogs at a football game. I can make a hot dog for $0.65 and sell it for $1.00. If i sell 50 hot dogs, what is my profit? show your work
Answer:
17.50
Step-by-step explanation:
The profit on one hotdog is
1 - .65 = .35
Multiply by the number of hotdogs sold
.35 * 50 =17.50
A marketing consulting group wants to see whether placing a seasonal cookie product on an end cap (the shelf at the end of an aisle at a store) will make a difference in sales. The average sales of the seasonal cookie for this region was 650 units. A sample of 36 stores that placed the cookie on an end cap showed a sample mean of 671 units sold with a standard deviation of 81. The resulting p-value is 0.1288; thus, the null hypothesis is not rejected. The marketing consulting group concludes that placing the cookies on an end cap does not affect sales. What type of error is possible in this situation
Answer:
Type II error.
Step-by-step explanation:
We have a hypothesis test for the claim that placing a seasonal cookie product on an end cap (the shelf at the end of an aisle at a store) will make a difference in sales.
The null hypothesis will state that there is no difference, while the alternative hypothesis will state that there is significant positive difference.
The result is a P-value of 0.1288 and the null hypothesis failing to be rejected.
As the null hypothesis failed to be rejected, if an error has been made in the conclusion, is that we erroneusly accept a false null hypothesis.
This is a Type II error, where the null hypothesis is accepted although the alternative hypothesis is true.
(a) Explain what is wrong with the following ‘proof’:Statement:IfRis symmetric and transitive, thenRis reflexive."Proof":SupposeRis symmetric and transitive. Symmetric means thatx R yimpliesy R x. We apply transitivity tox R yandy R xto givex R x. Therefore,Ris reflexive.(b) Give an example of a relation on a set that is both symmetric and tran-sitive, but not reflexive
Answer:
Step-by-step explanation:
Recall that, in this case, the subset of X for which R is defined is called the domain of R. The mistake occurs when we assume that the domain R is the whole set X, but it could happen that R is not defined for some elements of X.
Recall the following example:
X = {2,4,6}.
We can define R as follows {(2,2), (4,4), (2,4), (4,2)}. We can easily check that this is a transitive and symmetric relation, but since we don't have the element (6,6) it fails to be reflexive.
plsssssssssssssssss help
Answer:
60
Step-by-step explanation:
x=60 .
The triangle is equilateral and x=60 cause the two lines are ||
a. x=60°
b. Alternate interior angles
Solution,
Given,
All sides of triangle are equal.
AB=BC=AC
<ABC=<ACB=<BAC=y
By angle sum property of triangle,
<ABC+<BCA+<CAB=180
or y+y+y=180
or 3y=180
or y=180/3
y=60
Now,
<ACB=<CAD
<CAD(x)=60( Alternate interior angles)
Hope this helps ..
Good luck on your assignment..
Three support beams for a bridge form a pair of complementary angles. Find the measure of each angle. If (3x+3) (5x-9)
Answer:
39 degrees and 51 degrees respectively.
Step-by-step explanation:
Two angles are complementary if their sum adds up to 90 degrees.
Given the pair of complementary angles formed by the three support beams:
3x+3 and 5x-9
Then:
3x+3+5x-9=90 degrees
Collect like terms
3x+5x=90+9-3
8x=96
Divide both sides by 8
x=12
Therefore, the measure of each angle is:
[tex](3x+3)=3(12)+3=36+3=39^\circ\\(5x-9)=5(12)-9=60-9=51^\circ[/tex]
The measure of each angle is 39 degrees and 51 degrees respectively.
Answer:
39 and 51 degrees
Step-by-step explanation:
Which expression shows that the quotient {Read Attachment for full question}
Answer:
option 2
Step-by-step explanation:
2 / (3x - 1) ÷ 6 / (6x - 1)
= 2 / (3x - 1) * (6x - 1) / 6
= 1 / (3x - 1) * (6x - 1) / 3
= 6x - 1 / 9x - 3
Please answer this correctly
Answer:
# of plants # of gardens
10-14 2
15-19 2
20-24 5
25-29 3
30-34 3
35-39 5
40-44 4
Step-by-step explanation:
10-14: 10, 12 (2 numbers)
15-19: 18, 19 (2 numbers)
20-24: 20, 22, 23, 24, 24 (5 numbers)
25-29: 25, 27, 38 (3 numbers)
30-34: 31, 33, 33 (3 numbers)
35-39: 36, 36, 36, 37, 38 (5 numbers)
40-44: 40, 44, 44, 44 (4 numbers)
Answer:
10-14 ⇒ 2
15-19 ⇒ 2
20-24 ⇒ 5
25-29 ⇒ 3
30-34 ⇒ 3
35-39 ⇒ 5
40-44 ⇒ 4
find the equation of the line that is perpendicular to y= -1/5x-3 and contains the point (1,2) answer all boxes please
Answer:
Y = 5x -3
Step-by-step explanation:
Let's look for the gradient to solve this question for.
We are given y= -1/5x-3
Any line perpendicular to the above line will have a graient of m'.
Where mm'= -1
m = -1/5 from the line equation
So
mm'= -1
-1/5m'= -1
m' =5
For the equation of point (1,2)
(Y-y1)/(x-x1) = m'
(Y-2)/(x-1)= 5
Y-2= 5x -5
Y = 5x -3
Jack knows the surface area of a cylinder and its radius. He wants to find the cylinder's helght. He needs to rewrite the formula A = 2#r(+h)
to find the cylinder's height (h) In terms of the cylinder's surface area (A) and its radius (7). Which is the correct formula?
Answer:
h= pi(r)2/A or h= 3.14 times 7 times 2 divided by A
Step-by-step explanation:
u need to do the opposite of multiplication which is division to find the height
hope this helps
correct me if this is wrong
Find the distance from point B to point C.
Enter as a decimal rounded to the nearest tenth.
66°
5 mi
B
BC = [?] mi
Answer:
BC = 11.2 mi.
Step-by-step explanation:
Tan 66 = [tex]\frac{opposite }{adjacent}[/tex]
2.246 = [tex]\frac{BC}{5}[/tex]
=> BC = 5 × 2.246
=> BC = 11.2 mi.
Please please help me on this one!
Answer:
3422 x232
Step-by-step explanation:
Can advise on the solution?
Answer:
340
Step-by-step explanation:
If x is the amount of pages in the book we can write:
1/4x + 5 + 3/5(x - (1/4x + 5)) + 10 + 12 + 24 = x
1/4x + 51 + 3/5(3/4x - 5) = x
1/4x + 51 + 9/20x - 3 = x
7/10x + 48 = x
3/10x = 48
x = 160
The average American generates 4.4 lbs of trash every day. We circulated fliers that listed tips on how to reduce wastefulness in three separate neighborhoods. For the next week, we measured the amount of trash each person produced each day in those neighborhoods. There were 625 people total in our study. The mean trash per person was 4.3 lbs with a standard deviation of 1
Determine your sample's score on the comparison distribution.
a) -2
b) -1
c) -1.5
d) -2.5
Answer:
[tex]z= \frac{\bar X -\mu}{\frac{\sigma}{\sqrt{n}}}[/tex]
And replacing we got:
[tex] z=\frac{4.3 -4.4}{\frac{1}{\sqrt{625}}}= -2.5[/tex]
And the best option would be:
d) -2.5
Step-by-step explanation:
For this problem we know that the true mean of trash every day is:
[tex]\mu =4.4[/tex]
And from the info given we also know that:
[tex]\bar X=4.3[/tex] represent the sample mean
[tex]n=625[/tex] sample size selected
[tex]\sigma = 1[/tex] the population standard deviation assumed
If we want to find the z score for the person we can use the following formula:
[tex]z= \frac{\bar X -\mu}{\frac{\sigma}{\sqrt{n}}}[/tex]
And replacing we got:
[tex] z=\frac{4.3 -4.4}{\frac{1}{\sqrt{625}}}= -2.5[/tex]
And the best option would be:
d) -2.5