consecutives again

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consecutives again

by Johnrohit » Mon Oct 28, 2013 9:34 am
How many numbers are there between 1 and 101 which are multiples of either 5 or 7 or both 5
and 7?


36
34
32
20

[spoiler]OA=32[/spoiler]

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by theCodeToGMAT » Mon Oct 28, 2013 9:43 am
Multiple of "5" => 5 .... 100 = 20
Multiple of "7" => 7 .... 98 = 14

Common Multiples
5x7x1 = 35
5x7x2 = 70

So, Total numbers = 20+14-2 = 32
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by ganeshrkamath » Mon Oct 28, 2013 8:36 pm
Johnrohit wrote:How many numbers are there between 1 and 101 which are multiples of either 5 or 7 or both 5
and 7?


36
34
32
20

[spoiler]OA=32[/spoiler]
A = multiples of 5 between 1 and 101 = 20
B = multiples of 7 between 1 and 101 = 14
C = multiples of 7*5 between 1 and 101 = 2

Required sum = A + B - C = 20 + 14 - 2 = 32

Choose C

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