114k views
4 votes
A survey reported the number of meters (m) per week swam by two groups of swimmers—those who competed exclusively in breaststroke and those who competed in the individual medley (which includes breaststroke). The number of meters per week practicing the breaststroke was recorded for each swimmer, and the summary statistics are given below. Is there sufficient evidence to indicate that the average number of meters per week spent practicing breaststroke is greater for exclusive breaststrokers than it is for those swimming individual medley?

User Shears
by
4.5k points

2 Answers

7 votes

Answer:

Yes

Step-by-step explanation:

The data for both groups is missing in the question. It is shown in the attachment.

The data mentions sample size, mean and standard deviations of both the samples. This data can be used to test the hypothesis that "average number of meters per week spent practicing breaststroke is greater for exclusive breaststrokers than it is for those swimming individual medley".

Using the data, t-value, p-value and critical values can be determined

A survey reported the number of meters (m) per week swam by two groups of swimmers-example-1
User Rohit Maurya
by
4.0k points
1 vote

Complete Question:

A survey reported the number of meters (m) per week swam by two groups of swimmers—those who competed exclusively in breaststroke and those who competed in the individual medley (which includes breaststroke). The number of meters per week practicing the breaststroke was recorded for each swimmer, and the summary statistics are given below. Is there sufficient evidence to indicate that the average number of meters per week spent practicing breaststroke is greater for exclusive breaststrokers than it is for those swimming individual medley?

Specialty

Exclusive Breaststroke Individual Medley

Sample size 130 80

Sample mean (m) 9017 5853

Sample standard deviation (m) 7162 1961

Population mean
\mu_1
\mu_2

a. State the null and alternative hypothesis

b. What is the appropriate rejection region for an α = 0.01 level test?

c. Calculate the observed value of the appropriate test statistics

d. What is your conclusion?

e. What is a practical reason for the conclusion you reached in pat (d)?

Answer:

c. 4.76

Step-by-step explanation:

from the table shown above

let Y₁ be the number of meters (m) per week swum by those who competed exclusively in the Beast stroke

let Y₂ be the number of meters per week swum by those who competed in the individual medley

a)

Null hypothesis H₀:
\mu_1 = \mu_2

alternative Hypothesis H₁:
\mu_1 > \mu_2 (Right tailed test)

the attached images shows additional details of the solution

A survey reported the number of meters (m) per week swam by two groups of swimmers-example-1
A survey reported the number of meters (m) per week swam by two groups of swimmers-example-2
A survey reported the number of meters (m) per week swam by two groups of swimmers-example-3
A survey reported the number of meters (m) per week swam by two groups of swimmers-example-4
User Sujith Chandran
by
4.5k points