fraction comparison question

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fraction comparison question

by r_walid » Thu Oct 29, 2009 11:33 pm
if a,b,c, and d are positive integers, is (a/b) *(c/d) > c/b?

1- c>b
2- a>d

A-if 1 alone is sufficient
B-if 2 alone is sufficient
C- etc...


Can you please explain your reasoning?

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by jaspreet_takhar » Fri Oct 30, 2009 1:56 am
(a/b) *(c/d) > c/b
i:e ac/bd > c/b
as a b c d are +ve integers they are not equal to zero.
we can cancel c/b from both the sides.
which leaves us with finding out if a/d>1

in stmt 2, a>d , so 2 alone is suff.
stmt 1 doesnt give any info