# Can someone please answer these questions that is due 4/23//[email protected] 4pm please thank you. Chapter 6, Section 4-CI, Exercise 190 Use the t -distribution

Chapter 6, Section 4-CI, Exercise 190

Use the t

-distribution to find a confidence interval for a difference in means μ1-μ2

given the relevant sample results. Give the best estimate for μ1-μ2

, the margin of error, and the confidence interval. Assume the results come from random samples from populations that are approximately normally distributed.

A 95%

confidence interval for μ1-μ2

using the sample results x¯1=521

, s1=120

, n1=320

and x¯2=454

, s2=94

, n2=200

Enter the exact answer for the best estimate and round your answers for the margin of error and the confidence interval to two decimal places.

Best estimate =

Margin of error =

Confidence interval :

to

Chapter 6, Section 4-CI, Exercise 194

Does Red Increase Men’s Attraction to Women?

A study1 examines the impact of the color red on how attractive men perceive women to be. In the study, men were randomly divided into two groups and were asked to rate the attractiveness of women on a scale of 1

(not at all attractive) to 9

(extremely attractive). Men in one group were shown pictures of women on a white background while the men in the other group were shown the same pictures of women on a red background. The results are shown in Table 1 and the data for both groups are reasonably symmetric with no outliers.

Colorn

s

Red15

7.2

0.6

White12

6.1

0.4

Table 1 Does red increase men’s attraction to women?

To determine the possible effect size of the red background over the white, find a 95%

confidence interval for the difference in mean attractiveness rating μR-μW

, where μR

represents the mean rating with the red background and μW

represents the mean rating with the white background.

The 95%

confidence interval is

to

.

Chapter 6, Section 4-CI, Exercise 197

Effect of Splitting the Bill

A study compared the cost of restaurant meals when people pay individually versus splitting the bill as a group. In the experiment half of the people were told they they would each be responsible for individual meals costs and the other half were told the cost would be split equally among the six people at the table. The 24 people paying individually had a mean cost of 37.29 Israeli shekels with a standard deviation of 12.54, while the 24 people splitting the bill had a higher mean cost of 50.92 Israeli shekels with a standard deviation of 14.33. The raw data can be found in SplitBill and both distributions are reasonably bell-shaped. Use this information to find a 99%

confidence interval for the difference in mean meal cost between these two situations.

Click here