Bluebook SAT Test One-Variable Data: Distributions and Measures of Center and Spread 4

Question 1

The mean of five numbers is 14. Four of the numbers are 10, 12, 16, and 18. What is the fifth number?

Accepted Answer

14

Answer

The total sum must be 14 × 5 = 70; the known four sum to 56, so the fifth number is 70 − 56 = 14.

Question 2

A dot plot shows values: 1, 2, 2, 3, 3, 3, 4, 4, 5. What is the median?

Accepted Answer

3

Answer

With 9 values, the median is the 5th value when sorted, which is 3.

Question 3

A company reports employee salaries. The CEO earns $500,000 while most employees earn around $50,000. Which measure of center should HR use to most accurately represent the typical employee salary?

Accepted Answer

Median

Answer

The CEO's high salary would skew the mean upward, so the median better represents the typical employee salary.

Question 4

Dataset A: {1, 5, 5, 5, 9} and Dataset B: {3, 4, 5, 6, 7}. Which dataset has the greater standard deviation?

Accepted Answer

Dataset A

Answer

Both datasets have a mean of 5, but Dataset A's values (1 and 9) are farther from the mean than Dataset B's extremes (3 and 7), giving Dataset A a larger standard deviation.

Question 5

A box plot's median line is positioned closer to Q3 than to Q1. This suggests the distribution is:

Accepted Answer

Left-skewed

Answer

When the median is closer to Q3, the lower half of the data is more spread out, indicating a left-skewed distribution.

Bluebook SAT Practice Test

Bluebook SAT Practice Test

Bluebook SAT Test One-Variable Data: Distributions and Measures of Center and Spread 4