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 expected number of black squirrels she will see, E(X)?
A) 2.0
B) 2.5
C) 3.0
D) 3.5

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 expected number of black squirrels she will see, E(X)?
A) 2.0
B) 2.5
C) 3.0
D) 3.5

Quizplus · Accepted Answer

The expected number of black squirrels, E(X), for a binomial distribution is calculated as n*p, where n is the number of trials (5 squirrels) and p is the probability of success (seeing a black squirrel, 0.50). Therefore, E(X) = 5 * 0.50 = 2.5.

Use the Following Information for Questions