Question

A box contains 20 discs which are numbered from 1 to 20. If one disc is drawn at random from the box, then find the probability that the number the drawn disc is a number less than 10.

Answer 1

S = {1, 2, 3, 4, 5, ... 20}

∴ n(S) = 20

Number less than 10 = {1, 2, 3, 4, 5 ... 9}

Required probability = `9/20`