Use the following information for questions:
A child is observing squirrels in the park and notices that some are black and some are gray. For the next five squirrels she sees, she counts X = the number of black squirrels. Suppose X is a binomial random variable with n = 5 and p = 0.50.
-What is the variance for the number of black squirrels she will see, V(X)?
A) 1.00
B) 1.12
C) 1.25
D) 2.50

Question

Use the following information for questions:
 A child is observing squirrels in the park and notices that some are black and some are gray. For the next five squirrels she sees, she counts X = the number of black squirrels. Suppose X is a binomial random variable with n = 5 and p = 0.50.
-What is the variance for the number of black squirrels she will see, V(X)?
A) 1.00
B) 1.12
C) 1.25
D) 2.50

Quizplus · Accepted Answer

The variance of a binomial distribution is given by V(X) = n*p*(1-p), where n is the number of trials and p is the probability of success on each trial. Here, n = 5 and p = 0.50, so V(X) = 5*0.50*(1-0.50) = 1.25.

Use the Following Information for Questions