Portage Learning Math 110 Module 7 Exam

Portage Learning Math 110 Module 7 Exam

1. a) Define the null and alternative hypothesis for the following. Also, explain what it
would mean to make a Type I error and explain what it would mean to make a Type II
error.

The newspaper in a certain city had a circulation of 15,000 per day in 2010. You
believe that the newspaper’s circulation is more than 15,000 today.

b) Define the null and alternative hypothesis for the following. Also, explain what it
would mean to make a Type I error and explain what it would mean to make a Type
II error.

A certain website had 3500 hits per month a year ago. You believe that the number of
hits per month is less than that today.

a.
H0: μ =15,000

circulation H1: μ

>15,000 circulation

Type I error: Reject the null hypothesis that the mean of circulations is 15,000 even
though it is correct.

Type II error: Do not reject the null hypothesis when the mean of circulations is
greater than 15,000 circulations.

b.
H0:μ =3500

hits H1:μ <3500

hits

Type I error: Reject the null hypothesis even though the hits per month in a

year are at least 3500.

Type II error: Do not reject the null hypothesis when the mean of hits per

month is less than 3500.

, 2. Suppose that we have a problem for which the null and alternative hypothesis are
given by:

H 0:
μ=322.
H1:μ≠
322.

Is this a right-tailed test, left-tailed test, or two-tailed test. Find the z value based on a
level of significance of .06.

Two-tailed test

P(Z<z)=0.06/2=0.03 and P(Z>z)=0.06/2=0.03

z=-1.88 and z=1.88