Probability of drug companies obtainining permission for sale og a drg within 90 days is .75. If a sample of 5 compnanies selected what is the probability that none of them obtaine permission within 90 days.

Answer 1

prob of NOT getting permission = .25 = 1/4

so prob(no permission 5 times) = (1/4)^5
= 1/1024

Answer 2

THANKS A LOT...................