1. The distribution of household incomes for the American population is right skewed. If you create a sampling distribution of sample means using samples of size 65, what shape will it have?

Group of answer choices

right skewed

normal

uniform

Not enough information to tell.

left skewed

bimodal

2. You have constructed a confidence interval for the average weight of a calf (steers).

95% z CI: 60 lbs < m < 100 lbs

What is the Margin of Error?

Group of answer choices

95%

20 lbs

40 lbs

5%

We need to know the standard deviation and sample size to determine the margin of error.

80 lbs

2.5%

3. The average monthly mortgage payment including principal and interest is $996 in the United States. The standard deviation is approximately $162 and is normally distributed.

4. Find the probability that a randomly selected mortgage will have a monthly payment between $900 and $1000.

The average number of moves a person makes in his or her lifetime is 13 with a standard deviation of 2.3.

Find the probability that the mean of a sample of 36 people is between 13 and 14 moves.

5. A decibel is a measure of the intensity of sound. The mean number of decibels at large concerts is 120 with a standard deviation of 6 decibels. What is the probability that the next concert will have a decibel level less than 118?

6. A meteorologist wishes to estimate the mean speed of thunderstorms across the midwest. She samples 25 spring storms and finds the mean speed is 15.0 mph with a standard deviation of 1.7 mph. The population of speeds is normally distributed.

Construct an 95% confidence interval for the mean speed of all spring storms across the midwest.