EBook Problems Estim S Mean
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%.