Question

A box contain 20 balls bearing numbers 1,2,3,4,…………20. A ball is drawn at random from

the box. What is the probability that the number on the drawn ball is :

(i) An odd number

(ii) Divisible by 2 or 3​

Answer 1

i) There is a 50% probability/chance that odd number comes

ii) There is a 65% probability/chance that numbers divisible by 2 or 3 comes

Answer 2

Answer:

Given that,box contain 20 balls bearing numbers 1,2,3,4,…………20.

i.e sample space |S|= 20

(i) Let the event is coming an odd no. is 'E'

E = {1,3,5,7,9,11,13,15,17,19}

|E| = 10

:. The probability of getting an odd no.= |E|/|S|

=10 / 20 = 1/2

(ii) Let 'E' be the event is coming a no. which divisible by 2 or 3

|E| = {2,3,4,6,8,9,10,12,14,15,16,18,20}

|E| =13

:. The probability of getting a no. divisible by 2 or 3 = |E|/|S| = 13/20