Tickets numbered from 1 to 20 are mixed up together and then tickets are drawn at random. What is the probability that the ticket has a number which is a multiple of 3 or 7?

see full answer

Start JEE / NEET / Foundation preparation at rupees 99/day !!

21% of IItians & 23% of AIIMS delhi doctors are from Sri Chaitanya institute !!

An Intiative by Sri Chaitanya

115

12

25

720

answer is C.

(Unlock A.I Detailed Solution for FREE)

Ready to Test Your Skills?

Check your Performance Today with our Free Mock Test used by Toppers!

Take Free Test

Detailed Solution

Given, tickets numbered from 1 to 20 are mixed up together and then tickets are drawn at random.
The probability of an event occurring is calculated by dividing the number of favorable outcomes by the total number of events, that is,

Probability of an event = Number of favourable cases Total number of cases

Calculating the total number of possible outcomes-
The number of tickets from 1 to 20 is 20.
So, the total number of possible outcomes is 20.
To determine the number of favourable outcomes-
The numbers on the tickets that are multiples of 3 and 7 are 3, 6, 7, 9, 12, 14, 15, and 18.
As a result, the number of favourable outcomes is 8.
Finding the required probability by using the formula of probability that is,