The probability of a man hitting a target is 1 10 . The least number of shots required, so that the probability of his hitting the target at least once is greater than 1 4 , is....

Step-by-step solution

p = 1 10 ,   q = 9 10 P (not hitting in n trials) = 9 10 n ∴ P (at least one hit) = 1 − 9 10 n > 1 4 ⇒ 9 10 n < 3 4 0 .9 n < 0 . 75 If n = 3 ⇒ 0 . 729 < 0 . 75 which is true.