USA Today reports that about 25% of all prison parolees become repeat offenders.

USA Today reports that about 25% of all prison parolees become repeat offenders. Alice is a social worker whose job is to counsel people on parole. Let us say success means a person does not become a repeat offender. Alice has been given a group of four parolees.

(a) Find the probability P(r) of r successes ranging from 0 to 4. (Round your answers to three decimal places.)

P(0) = P(1) = P(2) = P(3) = P(4) = (b) Make a histogram for the probability distribution of part (a).

(c) What is the expected number of parolees in Alice’s group who will not be repeat offenders?

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What is the standard deviation? (Round your answer to two decimal places.)

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(d) What is the smallest group Alice can counsel to be at least 98% sure that three or more parolees will not become repeat offenders?

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