Chapter 2 MC

The heights of American men aged 18 to 24 are approximately Normally distributed with a mean of 68 inches and a standard deviation of 2.5 inches. Only about 5% of young men have heights outside the range

• 65.5 inches to 70.5 inches

• 63 inches to 73 inches

• 60.5 inches to 75.5 inches

• 58 inches to 78 inches

• none of the above

Tags

CCSS.HSS.ID.A.4

Use the information in the previous problem. About what percentage of the men are over 70.5 inches tall?

• 2.5

• 5

• 16

• 32

• 68

Tags

CCSS.HSS.ID.A.4

For the density curve shown, which statement is true?

• The area under the curve between 0 and 1 is 1

• The density curve is symmetric.

• The density curve is skewed right

• The density curve is Normal

• None of the above is correct.

Tags

CCSS.7.SP.C.7B

For the density curve shown, which statement is true?

• The mean and median are equal.

• The mean is greater than the median.

• The mean is less than the median

• The mean could be either greater than or less than the median.

• None of the above is correct

Tags

CCSS.6.SP.B.5D

CCSS.HSS.ID.A.2

The area under the standard Normal curve corresponding to –0.3 < Z < 1.6 is

• 0.3273

• 0.4713

• 0.5631

• 0.9542

• none of the above

Tags

CCSS.HSS.ID.A.4

The graph at right is a Normal probability plot for the amount of rainfall (in acre-feet) obtained from 26 randomly selected clouds that were seeded with silver oxide. Which of the following statements about the shape of the rainfall distribution is true?

• The distribution is Normal.

• The distribution is approximately Normal

• The distribution is skewed left

• The distribution has no potential outliers

• The distribution is skewed right.

The distribution of the time it takes for different people to solve a certain crossword puzzle is strongly skewed to the right, with a mean of 30 minutes and a standard deviation of 15 minutes. The distribution of z-scores for those times is

• Normally distributed, with mean 30 and standard deviation 15.

• Skewed to the right, with mean 30 and standard deviation 15.

• Normally distributed, with mean 0 and standard deviation 1.

• Skewed to the right, with mean 0 and standard deviation 1.

• Skewed to the right, but the mean and standard deviation cannot be determined without more information.

The cumulative relative frequency graph at right shows the distribution of lengths (in centimeters) of fingerlings at a fish hatchery. The interquartile range for this distribution is approximately:

• 0.18 to 0.85 centimeters

• 5 to 7 centimeters

• 5.5 to 6.7 centimeters

• 1.2 centimeters

• 2 centimeters

Tags

CCSS.6.SP.B.5C

Which of the following properties is true for all Normal density curves?

I. They are symmetric.

II. The curve reaches its peak at the mean.

III. 95% percent of the area under the curve is within one standard deviation of the mean.

• I only

• II only

• I and II only

• I and III only

• All three statements are correct

A fire department in a rural county reports that its response time to fires is approximately Normally distributed with a mean of 22 minutes and a standard deviation of 11.9 minutes. Approximately what proportion of their response times is over 30 minutes?

• 0.03

• 0.21

• 0.25

• 0.75

• 0.79

Tags

CCSS.HSS.ID.A.4