a) r is the product of 4 consecutive positive integers.
Multiples of 3 are 3,6,9,12...
any set of 4 positive integers will have a multiple of 3.
say 1,2,3,4 has 3
8,9,10,11 has 9(a multiple of 3)
Hence a) alone is sufficent
b) r < 25
It doesnt matter if r is less than 25 or not.
Hence A is the correct choice
Cheers!
Aks
DS integers-divisible
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akshatsingh
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Neo2000
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If the integer is n, 4 consecutive integers become
n n+1 n+2 n+3 and n+4
For any given number, if you consider it as a part of 4 consecutive numbers then you will always be able to divide it by 3
Hence only 1 is sufficient
n n+1 n+2 n+3 and n+4
For any given number, if you consider it as a part of 4 consecutive numbers then you will always be able to divide it by 3
Hence only 1 is sufficient
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simplyjat
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As a general rule.
If a number is a product of N consecutive numbers, it would be completely divisible by all number from 1 to N.
So if a number is a product of four consecutive numbers, then the number is completely divisible by 1, 2, 3 and 4....
If a number is a product of N consecutive numbers, it would be completely divisible by all number from 1 to N.
So if a number is a product of four consecutive numbers, then the number is completely divisible by 1, 2, 3 and 4....
Last edited by simplyjat on Mon Apr 28, 2008 11:36 am, edited 1 time in total.
simplyjat
