The Magazine Mass Marketing Company has received 15 entries

The Magazine Mass Marketing Company has received 15 entries in its latest sweepstakes. They know that the probability of receiving a magazine subscription order with an entry form is 0.5. PROBABILITY What is the probability that less than 4 of the entry forms will include an order? Answer: (Round your answer to 3 decimal places) Q6.5

Solution

Binomial with n = 16 and p =0.5

P(X=r) = 16Cr*0.5^r*0.5^(16-r)

P( 7 <= X <= 10) = P(X<=10) - P(X<7)

= 0.895-0.227 = 0.668