Question

1a. A particular telephone number is used to receive both voice calls and fax messages. Suppose that 20% of the incoming calls involve fax messages, and consider a sample of 20 incoming calls. (Round your answers to three decimal places.)

(a) What is the probability that at most 6 of the calls involve a fax message?

  

(b) What is the probability that exactly 6 of the calls involve a fax message?

  

(c) What is the probability that at least 6 of the calls involve a fax message?

  

(d) What is the probability that more than 6 of the calls involve a fax message?

1b. Compute the following binomial probabilities directly from the formula for b(x; n, p). (Round your answers to three decimal places.)

(a)

b(5; 8, 0.25)

  

(b)

b(6; 8, 0.65)

  

(c)

P(3 ≤ X ≤ 5)

when n = 7 and p = 0.65

  

(d)

P(1 ≤ X)

when n = 9 and p = 0.15

Answer 1