# Exam 3 Study Guide: Chapters 5-6

1. You are given a table with columns for the z-score, area to the left of the z-score, area to the right of the z-score, and twice the smaller area. You will be given one piece of information (anything but twice the smaller area) and asked to find the other values. Four parts.
2. A confidence interval for the population proportion is given. Find the sample proportion and the margin of error.
3. 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. This is straight from the Central Limit Theorem.
4. 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.
5. 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.
6. Find the sample size needed to estimate a population proportion. The formula is provided. Be sure you write percents as decimals when you're using the formulas. Remember that the sample size must be rounded up to the next whole number.
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. Find the sample size needed to estimate a population mean. The formula is provided. Remember that the sample size must be rounded up to the next whole number.
9. 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. Labe the graph to illustrate the 68-95-99.7 rule. Find the probability of an individual having a particular score. Find the raw scores based on the probabilities.
10. 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 t table, not the sample size.
11. 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.
12. The mean and standard deviation for a non-standard normal distribution is given. Find the probability of one randomly selected individual having a certain value. Find the raw score that goes along with a certain probability. Find the probability of the mean of a group having a particular value. Find the standard error of the mean.
13. Use the standardization formula for an individual value to find the missing values. A table is given with three of the four variables (x, z, μ, and σ) supplied and you're asked to find the fourth. Four parts.

## 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 12 4 4 8 8 3 21 3 9 5 5 10 8 100