How many numbers between 1 and 100 (inclusive) are divisible by 10 or 7?

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19 Feb 2018 Divisibility

How many numbers between 1 and 100 (inclusive) are divisible by 10 or 7?

OPtion

1) 25
2) 26
3) 24
4) 22
5) 23
6) 22
7) 21
8) 27
9) 20
10) None of these

Solution

There are 10 numbers divisible by 10 between 1 and 100, and 14 numbers divisible by 7 between 1 and 100.

So there are 10 + 14 = 24, so 24 numbers divisible by one or the other, but this also includes every number which is divisible by both 7 and 10 twice.
Only one such number between 1 and 100 which is divisible both by 7 and 10 is 70

So answer is 10+14-1 = 23

Correct Option: 5 Best Solution (0)