A die is rolled nine times and the number of times that two shows on the upper face is counted. If this experiment is repeated many times, find the mean for the number of twos.
A) 1.5 twos
B) 3 twos
C) 7.5 twos
D) 2.25 twos

Question

Quizplus · Accepted Answer

The probability of rolling a two on a die is 1/6. If a die is rolled nine times, the expected number of twos is 9 * (1/6) = 1.5 twos.

A Die Is Rolled Nine Times and the Number of Times