In a test of physical fitness, a group of men ages 65 and older from a local ret

ID: 3133383 • Letter: I

Question

In a test of physical fitness, a group of men ages 65 and older from a local retirement community were told to do as many sit-ups as they could. It is known the population mean ^mu is 20 with sigma x^-8. The scores for the men from the retirement community are given below. What is the standard error of the mean? a. 1.25 b. 4.00 c. 0.5 d. 2.00 14. In a test of physical fitness, a group of men ages 65 and older from a local retirement community were told to do as many sit-ups as they could, it is known the population mean^mu is 20 with sigma x^-8. the scores for the men from the retirement community are given below. What is the z-value? a. 1.25 b. 2.25 c. 5.50 d. 1.50 15. Given the z-score you obtained in problem #14 and use a two - tailed rejection region with a total area of 0.05, what can we say about this sample's mean? a. Since the z-value falls within the region of rejection, we should not conclude this sample mean likely represents some other population b. Since the z-value falls within the region of ejection, we should conclude this sample mean represents some other population. c. Since the z-value falls within the region of rejection, we should conclude this sample mean likely represents some other population. d. Since the z-value falls within the region of rejection, we should not conclude this sample mean likely represents some other population.

Explanation / Answer

Solution: (13)

Standard error of the mean = 2.00

Correct answer: (d) 2.00

Solution: (14)

Z-value = 2.25

Correct answer: (b) 2.25

Solution: (15)

Correct answer: (c) since the z value falls within the region of rejection, we should conclude that this sample mean represents some other population.

Z Test of Hypothesis for the Mean

Data

Null Hypothesis m=

Level of Significance

0.05

Population Standard Deviation

Sample Size

Sample Mean

24.5

Intermediate Calculations

Standard Error of the Mean

2.0000

Z Test Statistic

2.2500

Two-Tail Test

Lower Critical Value

-1.9600

Upper Critical Value

1.9600

p-Value

0.0244

Reject the null hypothesis