Question

A standard die is rolled 360 times in hopes of rolling a 5 or 6. So the probability of success is p=1/3. Find the standard deviation of the binomial distribution.
8.9
80.0
119.9
0.2

Answer 1

Answer: option 1 is the correct answer

Step-by-step explanation:

Number of times for which the die was rolled is 360. It means that our sample size, n is 360.

The probability of rolling a 5 or a 6 is 1/3. It means that probability of success,p = 1/3. The probability of failure,q is

1 - probability of success. It becomes

1 - 1/3 = 2/3

The formula for standard deviation is expressed as

√npq. Therefore

Standard deviation = √360 × 1/3 × 2/3

= √80 = 8.9443

Standard deviation is approximately 8.9