try plugging in

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try plugging in

by sanju09 » Thu May 07, 2009 5:28 am
If a b = 5, b c = 10 and c d = 13, then a d =
A. 650
B. 65
C. 26
D. 50/13
E. 13/2


OA E
Last edited by sanju09 on Sat May 09, 2009 5:47 am, edited 1 time in total.
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by scoobydooby » Thu May 07, 2009 5:34 am
ab/bc=1/2
=>a/c=1/2
=>c=2a

given cd=13
=>2a*d=13
=>ad=13/2

hence, E