PS Problem

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PS Problem

by majsandip » Wed May 07, 2008 8:41 pm
If x and y are consecutive positive integer multiples of 3, what is the greatest integer J such that xy/J is always an integer?
a) 27
b) 18
c) 9
d) 6
e) 3.

My ans a.
Right choice B :shock:

Since the Ques stem says consecutive +ve integer it may be 3,6 or 6,9 or 12,15.......???
lived by chance!!
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by akshatsingh » Wed May 07, 2008 11:13 pm
If x and y are consecutive positive integer multiples of 3, what is the greatest integer J such that xy/J is always an integer?
a) 27
b) 18
c) 9
d) 6
e) 3.


xy/J always has to be an integer.

if you take 3 and 6, as x and y respectively and J as 27, xy/J wont be an integer.

J should be 3*6 for all other products of multiples to be an integer when divided by J.

Hope this clears your doubt..
Aks

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by camitava » Thu May 08, 2008 12:18 am
Agree with Aks. IMO B. The example shown by Aks shows the reason why j has to be equal to 18?
Correct me If I am wrong


Regards,

Amitava