Aptitude Day 136

Problems on Probability:

1. Tickets numbered 1 to 30 are mixed up and then a ticket is drawn at random. What’s the probability that the ticket drawn has a number which is a multiple of 4 or 6?

Solution:

                n(S) = 30

                 E = {4, 8, 12, 16, 24, 28, 6, 18, 30}

                 P(E) = n(E)/ n(S)

                         = 10/36

                         = 5/18.

2. In a lottery, there are 5 prizes and 10 blanks. A lottery is drawn at random. What’s the probability of getting a prize?

Solution:

                 n(S) = 5 + 10 =15.

                 P(E) = n(E)/ n(S)

                         = 5/15

                         = 1/3.