# EBook Problems Estim S Mean

Jump to: navigation, search

## EBook Problems Set - Estimating a Population Mean: Small Samples Problems

### Problem 1

A random sample of 121 students from the UCLA was selected to estimate the average ACT score of all UCLA students. The average for the sample was 23.4 and the sample standard deviation was 3.65. If you wanted to calculate a more precise and accurate prediction of the average ACT score of UCLA students, which one of the following would be the best thing to do?

• Choose one answer.
(a) Decrease the sample size to 91.
(b) Increase the sample size to 151.
(c) Increase the confidence level to 99%.
(d) Decrease the confidence level to 90%.

### Problem 2

The average standardized math score for eighth graders in the state of California is 70 and the standard deviation is 10. We want to find out if the average standardized math score in district A is higher than the average score for the state of California. The mean for a random sample of 36 students from this district is 72.

What is the best response?

• Choose one answer.
(a) The p-value is around 0.76 and it is concluded that the average standardized math score in this district is not different from the overall population mean.
(b) The p-value is around 0.12 and it is concluded that the average standardized math score in this district is not higher than the overall population mean.
(c) The p-value is around 0.24 and it is concluded that the average standardized math score in this district is not higher than the overall population mean.
(d) The p-value is around 0.88 and it is concluded that the average standardized math score in this district is not higher than the overall population mean.

Translate this page: