# A number is selected from first 50 natural numbers.

Question:

A number is selected from first 50 natural numbers. What is the probability that it is a multiple of 3 or 5?

(a) $\frac{13}{25}$

(b) $\frac{21}{50}$

(c) $\frac{12}{25}$

(d) $\frac{23}{50}$

Solution:

GIVEN: A number is selected from 50 natural numbers

TO FIND: Probability that the number selected is a multiple of 3 or 5

Total number is 50

Total numbers which are multiple of 3 or 5 up to 50 natural numbers are

3,6,5,9,10,12,15,18,20,21,24,25,27,30,33,35,36,39,40,42,45,48,50

Total number which are multiple of 3 or 5 up to 50 natural numbers are23

We know that PROBABILITY =

Hence probability that the number selected is a multiple of 3 or 5 is equal to