Chapter 11.2, Problem 61E

a)

To determine

To explain which test will be applicable from inference.

Answer to Problem 61E

One-sample t interval for the mean should be used.

Explanation of Solution

Given:

What is the average voter turnout during an election? A random sample of 33 cities was asked to report the percent of registered voters who voted in the most recent election.

First, we need to list which hypothesis tests we learnt.

Z-test or interval of proportion for one sample. Z-test or interval of proportion for two sample. T-test or interval of mean for one sample. T-test or interval of mean for two sample. Paired t-test of mean for two sample. Chi-square test of independence or Homogeneity.

For given example, need to check average voter. That means interested in average of one sample. Therefore, one-sample t interval for the mean should be used.

b)

To determine

To explain which test will be applicable from inference.

Answer to Problem 61E

Z-test of proportion for two sample should be used.

Explanation of Solution

Given:

Are blondes more likely to have a boyfriend than the rest of the single world? Independent random samples of 300 blondes and 300 nonblondes were asked whether they have a boyfriend.

First, we need to list which hypothesis tests we learnt.

Z-test or interval of proportion for one sample. Z-test or interval of proportion for two sample. T-test or interval of mean for one sample. T-test or interval of mean for two sample. Paired t-test of mean for two sample. Chi-square test of independence or Homogeneity.

For given example, need to check increases in the difference of two proportion of two sample. Therefore, Z-test of proportion for two sampleshould be used.