# Exam 3 Study Guide: Chapters 5-6

1. You are given the area to the left of a critical z-score. Find the area to the right, determine whether or not the value lies on the left side or right side of zero, and look up the z-score in the table.
2. You are given the area to the right of a critical z-score. Find the area to the left, determine whether or not the value lies on the left side or right side of zero, and look up the z-score in the table.
3. A confidence interval for the population proportion is given. Find the sample proportion and the margin of error.
4. A population mean and standard deviation are given along with a sample size. Determine the mean and standard deviation for the sampling distribution of the sample means.
5. A sample size and a confidence interval for the population mean are supplied. Find the sample mean, the margin of error, the standard error the means, and the sample standard deviation.
6. A sample size and number of successes is given. Find the sample proportion, the standard error for the sample proportion, the margin of error, and the confidence interval.
7. Standard normal probabilities. Draw vertical line(s) at the indicated z-scores and shade the described region. Then use the standard normal table to find the area of the described region. The curve is supplied, you just need to label and shade it. Seven parts. Look at problems 5.2.9-28, 33-36.
8. The population mean and standard deviation for a non-standard normal distribution are given. Label a normal curve with the appropriate values for the tick marks. Find the probability of an individual having a particular score. Find the probability of the mean of a sample having a particular score. Find the raw scores based on the probabilities.
9. Look up the critical values using the normal or t tables. Remember that when the critical value notation is used, it is always the right tail area that is given. Five parts. Remember that the df=n-1 for the t distribution and it's the df you lookup in the table, not the sample size.
10. Find the sample size needed to estimate a population proportion. The formula is provided.
11. Find the sample size needed to estimate a population mean. The formula is provided.
12. The results of a public opinion poll are given. Read the results and determine the sample proportion, margin of error, confidence level, and confidence interval.
13. A raw score and percentile are given for a normal distribution. Use the percentile to find the z-score. Then find the mean of the distribution (the standard deviation is supplied).

## Notes

• You will need a calculator for the test.
• The formulas for the mean and standard error of the sample proportion and sample mean are given on the test. A generic formula for margin of error is also given. You will need to know when and how to use the formulas, though.
• The standard normal and t-tables will be supplied with the test.

## Points per problem

 # Pts 1 2 3 4 5 6 7 8 9 10 11 12 13 Total 5 5 4 4 8 8 21 15 10 3 3 8 6 100