Question

For an initial screening of an admission test, a candidate is given fifty problems to solve. If the probability that the candidate solve any problem is  4/5 , then the probability that he is unable to solve less than two problems is :

(1)  164/25(1/5)⁴⁸

(2)  316/25(4/5)⁴⁸

(3)   201/5(1/5)⁴⁹

(4)  54/5(4/5)⁴⁹

Answer 1

Correct option  (4)  54/5(4/5)⁴⁹

Explanation:

Total problems = 50

P(Solving) =  4/5

P(Not solving) = 1/5

P(unable to solve less than two problems) = P(not solving one problem) + P(not solving zero problem)