Solve the problem.
-A die is rolled 15 times and the number of twos that come up is tallied. If this experiment is repeated many times, find the standard deviation for the number of twos.
A)1.394
B)1.449
C)1.94
D)1.443

Question

Quizplus · Accepted Answer

The standard deviation for the number of twos is the square root of the variance, which is the product of the probability of getting a two and the probability of not getting a two, multiplied by the number of rolls. The probability of getting a two is 1/6, and the probability of not getting a two is 5/6. Therefore, the variance is (1/6) * (5/6) * 15 = 1.443. The standard deviation is the square root of 1.443, which is 1.443.

Solve the Problem. -A Die Is Rolled 15 Times and the Number of the Number