Question

A box contains 30 tickets, bearing only one number from 1 to 30 on each. If one ticket is drawn at random, find the probability of an event that the ticket drawn bears 

i. an odd number. 

ii. a complete square number.

Answer 1

Sample space, 

S = {1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29, 30} 

∴ n(S) = 30

i. Let A be the event that the ticket drawn bears an odd number.

∴ A = {1, 3, 5, 7, 9, 11, 13, 15, 17, 19, 21, 23, 25, 27, 29}

∴ n(A) = 15

ii. Let B be the event that the ticket drawn bears a complete square number.

∴ B = {1, 4, 9, 16, 25} 

∴ n(B) = 5