Posted by **Marshall** on Thursday, November 6, 2008 at 3:10pm.

The scores of students on the ACT college entrance examination in a recent year had a normal distribution with a mean of 18.6 and a standard deviation of 5.9. A simple random sample of 50 students who took the exam is selected for study:

A) What is the shape, mean, and standard deviation of the sampling distribution

of the sample mean for samples of size 50?

B) What is the probability that the sample mean is 21 or higher?

C) What is the probability that the sample mean falls within 2 points of the

population mean?

D) What is the probability that the sample mean is 17 or less?

Last year, a national opinion poll found that 44% of all American adults agree that parents should be given vouchers good for education at any public or private school of their choice. Assume that in fact the population proportion is 0.44. A sample of 300 is to be selected and asked the same question:

A) What is the shape, mean, and standard deviation of the sampling distribution

of the sample proportion for samples of size 300?

B) What is the probability that the sample proportion will fall within 3% of the

population proportion?

C) What is the probability that the sample proportion will exceed 50%?

D) If the sample size were increased to 900, what is the probability that the

sample proportion will fall within 3% of the population proportion

- statistics -
**Cori**, Wednesday, November 12, 2008 at 5:10pm
13.2555

- statistics -
**cj**, Saturday, April 4, 2009 at 5:56pm
7.62

## Answer This Question

## Related Questions

- AP Statistics - Sampling Distribution Help - The composite scores of students on...
- AP Statistics - sampling distribution help - The composite scores of students on...
- AP - The composite scores of students on the ACT college entrance examination in...
- Statistics - 1. The scores of students on the ACT college entrance examination ...
- Algebra - Over 350 students took a college calculus final exam. the scores of ...
- statistics - The Survey of Study Habits and Attitudes (SSHA) is a psychological ...
- Foundations of Measurement - Approximately 400,000 students took the GRE in 2009...
- statistics - The Survey of Study Habits and Attitudes (SSHA) is a psychological ...
- statistics - Scores on a certain nationwide college entrance examination follow ...
- math - Statistics: Analyze student exam scores Students were given an exam with ...

More Related Questions