SOLUTION: one-fifth of all jellybeans are black. A random sample of ten jellybeans is chosen. What is the probability that this sample contains exactly two jellybeans? What is the proba

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Question 1149900: one-fifth of all jellybeans are black. A random sample of ten jellybeans is chosen.
What is the probability that this sample contains exactly two jellybeans?
What is the probability that it contains fewer than two black beans?

Answer by Boreal(15235) About Me  (Show Source):
You can put this solution on YOUR website!
binomial with n=10 p=0.2
exactly 2 is 10C2*0.2^2*0.8^8=0.3020
fewer than 2 include 0 and 1
probability of 0 is 0.8^10=0.1074
probability of 1 is 10*0.2*0.8^9, the 10 being the number of ways it can happen=0.2684
that is the sum of those two values or 0.3758