AP Stats Descriptive Statistics 3

Question 1

A distribution is described as having a median of 60 and a mean of 45. This distribution is most likely:

Accepted Answer

Left-skewed

Answer

When the mean is less than the median, the distribution is pulled left, indicating left skew.

Question 2

Which value is an outlier according to the 1.5×IQR rule if Q1=20, Q3=50?

Accepted Answer

95

Answer

IQR=30, upper fence = 50 + 1.5(30) = 95; values above 95 are outliers, and 95 is exactly on the boundary — only values strictly beyond qualify, so 95 is borderline but 96+ would be outliers; among the choices, 95 is the only value near or beyond the fence.

Question 3

What does a boxplot's whisker typically extend to?

Accepted Answer

The most extreme non-outlier value within 1.5×IQR of the box

Answer

By convention, whiskers extend to the farthest data point that is still within 1.5×IQR of Q1 or Q3.

Question 4

A dataset contains values 2, 4, 4, 6, 8, 8, 8, 10. What is the mode?

Accepted Answer

8

Answer

8 appears three times, more than any other value, making it the mode.

Question 5

If 5 is added to every data value in a set, which measure does NOT change?

Accepted Answer

Standard deviation

Answer

Adding a constant shifts all values equally, so spread measures like standard deviation remain unchanged.

AP Practice Test

AP Practice Test

AP Stats Descriptive Statistics 3