A box contains 13 transistors 3 of which are defective If 3

A box contains 13 transistors, 3 of which are defective. If 3 are selected at random, find the probability that a. All are defective. b. None are defective.

Solution

Probabaility of defective transistors = 3/13

Probabaility of not defective transistors = 10/13

If 3 are selected at random

a) all are defective = (3/13)^3 = 0.0122

b) none are defecetive = (10/13)^3 = 0.4551