College Math Placement Test Statistics 2

Question 1

A dataset has values 4, 8, 6, 5, 3, 2, 8, 9, 8, 1. What is the mode?

Accepted Answer

8

Answer

The mode is 8 because it appears 3 times, more than any other value.

Question 2

Which measure of central tendency is most affected by extreme outliers?

Accepted Answer

Mean

Answer

The mean is most affected by outliers because it uses every value in its calculation.

Question 3

A sample of 5 test scores has a variance of 36. What is the standard deviation?

Accepted Answer

6

Answer

Standard deviation is the square root of variance, so √36 = 6.

Question 4

In a normal distribution, approximately what percentage of data falls within one standard deviation of the mean?

Accepted Answer

68%

Answer

The empirical rule states that about 68% of data falls within one standard deviation of the mean.

Question 5

A bag contains 4 red, 3 blue, and 5 green marbles. What is the probability of drawing a blue marble?

Accepted Answer

3/12

Answer

There are 3 blue out of 12 total marbles, so P(blue) = 3/12 = 1/4.

College Math Placement Test Practice Test