1answer.
Ask question
Login Signup
Ask question
All categories
  • English
  • Mathematics
  • Social Studies
  • Business
  • History
  • Health
  • Geography
  • Biology
  • Physics
  • Chemistry
  • Computers and Technology
  • Arts
  • World Languages
  • Spanish
  • French
  • German
  • Advanced Placement (AP)
  • SAT
  • Medicine
  • Law
  • Engineering
Tresset [83]
3 years ago
9

A paper describes a study in which researchers observed wait times in coffee shops in Boston. Both wait time and gender of the c

ustomer were observed. The mean wait time for a sample of 145 male customers was 85.8 seconds. The mean wait time for a sample of 141 female customers was 113.4 seconds. The sample standard deviations (estimated from graphs that appeared in the paper) were 50 seconds for the sample of males and 75 seconds for the sample of females. For purposes of this exercise, suppose that these two samples are representative of the populations of wait times for female coffee shop customers and for male coffee shop customers. Is there convincing evidence that the mean wait time differs for males and females? Test the relevant hypotheses using a significance level of 0.05. (Use a statistical computer package to calculate the P-value. Use μmales − μfemales. Round your test statistic to two decimal places, your df down to the nearest whole number, and your P-value to three decimal places.)
Mathematics
1 answer:
kvasek [131]3 years ago
4 0

Answer:

t=\frac{85.8-113.4}{\sqrt{\frac{(50)^2}{145}+\frac{(75)^2}{141}}}}=-3.65  

p_v =2*P(t_{(284)}

Using Excel we can use the following code: "=2*T.DIST(-3.65;284;TRUE)"

So the p value is a very low value and using any significance level giveen \alpha=0.05 always p_v so we can conclude that we have enough evidence to reject the null hypothesis, and there is enough evidence to conclude that the means are different.

Step-by-step explanation:

1) Data given and notation

\bar X_{M}=85.8 represent the mean for the males

\bar X_{F}=113.4 represent the mean for females

s_{M}=50 represent the sample standard deviation for males

s_{F}=75 represent the sample standard deviation for female

n_{M}=145 sample size for the group poisoned

n_{F}=141 sample size for the group unpoisoned

t would represent the statistic (variable of interest)

2) Concepts and formulas to use

We need to conduct a hypothesis in order to check if the mean for the two groups are equal or not , the system of hypothesis would be:

Null hypothesis:\mu_{M} = \mu_{F}

Alternative hypothesis:\mu_{M} \neq \mu_{F}

If we analyze the size for the samples both are higher than 30 but the population deviations are not given, so for this case is better apply a t test to compare means, and the statistic is given by:

t=\frac{\bar X_{M}-\bar X_{F}}{\sqrt{\frac{s^2_{M}}{n_{M}}+\frac{s^2_{F}}{n_{F}}}} (1)

t-test: Is used to compare group means. Is one of the most common tests and is used to determine whether the means of two groups are equal to each other.

3) Calculate the statistic

We can replace in formula (1) the results obtained like this:

t=\frac{85.8-113.4}{\sqrt{\frac{(50)^2}{145}+\frac{(75)^2}{141}}}}=-3.65  

4) Statistical decision

The first step is calculate the degrees of freedom, on this case:

df=n_{M}+n_{F}-2=145+141-2=284

Since is a two tailed test the p value would be:

p_v =2*P(t_{(284)}

Using Excel we can use the following code: "=2*T.DIST(-3.65;284;TRUE)"

So the p value is a very low value and using any significance level giveen \alpha=0.05 always p_v so we can conclude that we have enough evidence to reject the null hypothesis, and there is enough evidence to conclude that the means are different.

You might be interested in
Which translation will change figure ABCD to figure A′B′C′D′? (5 points)
mylen [45]
6 units to the left and 7 units down will get you A'B'C'D
6 0
2 years ago
What’s 2-3-4-4+7. Plzzzz
nignag [31]

Answer:

-2

Step-by-step explanation:

Simplify the following:

2 - 3 - 4 - 4 + 7

2 - 3 - 4 - 4 + 7 = (2 + 7) - (3 + 4 + 4):

(2 + 7) - (3 + 4 + 4)

2 + 7 = 9:

9 - (3 + 4 + 4)

3 + 4 = 7:

9 - (7 + 4)

7 + 4 = 11:

9 - 11

9 - 11 = -2:

Answer:  -2

6 0
3 years ago
Read 2 more answers
Pls help I hate math rectangular prism
nekit [7.7K]

Answer:

352.5cm^{2}

Step-by-step explanation:

A=3Rectangles+2Triangles\\=3*7.5*13.5+2*.5*6.5*7.5=352.5cm^{2}

8 0
2 years ago
How do I solve -12+1/2x=-6​
dedylja [7]

Answer:

x = 12

Step-by-step explanation:

First, eliminate the fractional coefficient 1/2, by multiplying all three terms by 2:

-24 + x = -12

Adding 24 to both sides isolates x:  x = -12 + 24, or x = 12

6 0
2 years ago
Your goal this year is to earn a B or better in Algebra
svlad2 [7]
Wow that’s a lot of money for getting a B,if I don’t get 95 percent A in any of my classes I won’t be able to walk after my mom finds out.
6 0
3 years ago
Other questions:
  • Can someone answer this Algebra question asap? thanks!!<br> A) -4<br> B) -1/4<br> C) 1/4<br> D) 4
    15·2 answers
  • In ΔABC, ∠A = 72 and ∠B = 18. What is the shortest side of the triangle?
    13·1 answer
  • Was the ratio of 2:7 equivalent to
    6·2 answers
  • I forgot about scientific notation
    6·1 answer
  • a dream club charges $150 for the first month of membership, and $5 less each month after that. what is the total membership for
    12·1 answer
  • Hey guys im back with some new math content help plz
    6·1 answer
  • Simplify the expression: 5-−3ℎ −(6-+7ℎ)<br> a) 11-−4ℎ <br> b) 11-−10ℎ <br> c) −-−4ℎ <br> d) −-−10ℎ
    12·1 answer
  • (MARKING) How many solutions does this equasion have? -4 - 10n = 8h + 10
    12·2 answers
  • 30÷4<br><br><br><br>pls show the working ​
    7·2 answers
  • Choose the three equivalent forms of 4.625.
    10·2 answers
Add answer
Login
Not registered? Fast signup
Signup
Login Signup
Ask question!