Question

he mean age of graduate students at a University is thought to be 31 years old.

A random sample of 15 graduate students is taken. The sample mean age is 33 years and the sample standard deviation is three years.

Does the sample data indicate that the population mean age is actually greater than 31 years old? Use a 1% level of significance.

a.) What is α? State the null and alternate hypotheses. Will you use a left-tailed, right-tailed, or two-tailed test?

αα =

H0H0: μμ =

H1H1: μμ Select an answer > < not =  

The test is a Select an answer two-tailed right-tailed left-tailed  test

b.) Identify the Sampling Distribution you will use. What is the value of the test statistic?

The best sampling distribution to use is the Select an answer Normal Student's t  distribution.

The test statistic (z or t value) is =

c.) Find or estimate the P-value for the test.

The p-value is = Select an answer Between 0.025 and 0.050 Between 0.100 and 0.125 Between 0.075 and 0.100 Between 0.050 and 0.075 Between 0.010 and 0.025

d.) Conclude the test.

Based on this we will Select an answer Reject Fail to reject  the null hypothesis.

LicensePoints possible: 16

Answer 1

This is the right tailed test .

The null and alternative hypothesis is

H₀ : = 31

H_a : > 31

Test statistic = t

= ( - ) / s / n

= (33 - 31) / 3 / 15

Test statistic = 2.582

df = 15 - 1 = 14

Between 0.010 and 0.025

  

P-value >

Fail to reject the null hypothesis .