Question

Find the number of numbers between 1 and 100 both inclusive that are divisible by 3 or 5

Answer 1

Answer:

47

Step-by-step explanation:

SolutionThere are 20 numbers divisible by 5 between 1 and 100, and 33 numbers divisible by 3 between 1 and 100.

So there are 20 + 33 = 53, so 53 numbers divisible by one or the other, but this also includes every number which is divisible by both 5 and 3 twice.

Such numbers are 15, 30 and so on multiples of 15 between 1 to 100

There are 6 numbers divisible by 15 between 1 and 100 (i.e divisible by both 3 and 5)

So answer is 20+33-6 = 47

Answer 2

Question

Find the number of numbers between 1 and 100 both inclusive that are divisible by 3 or 5

Answer

Given:-

The number of numbers Which are both

Divisible by 3 and 5

To Find :-

The numbers which are divisible by 3 and 5

Solution of the question :-

To be divisible by 3 and 5 simultaneously, a number has to be divisible by

15 (3x5).

Between 1 and 100, there are

100/15=6.66 and so 6 numbers (you can check that by multiplying 15 by 6 and 7 which gives us 90 and 105 respectively)-15,30,45,60,75 and 90.