Question

In a shipment of 58 vials, only 13 do not have hairline cracks. if you randomly select 4 vials from the shipment, what is the probability that all 4 of the selected vials have hairline cracks?g

Answer 1

For this problem, we use the repeated trials equation:

P = n!/r!(n-r)!*p^(n-r)*q^r
where
P is the total probability of having r successful trials out of the total n trials. p is equal to 13/58, while q is equal to 1 - 13/58.

P = 4!/4!(4-4)!*(13/58)^(4-4)*(1 - 13/58)^4
P = 0.362 or 36.2%