VIC

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VIC

by joyseychow » Thu Jul 16, 2009 1:58 am
In a certain formula, p is directly proportional to s and inversely proportional to r. If p =1 when r = 0.5 and s = 2, what is the value of p in terms of r, and s?

(A)s/r
(B)r/4s
(C)s/4r
(D)r/s
(E)4r/s

Pls. explain. I don't understand the ques.

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by tohellandback » Thu Jul 16, 2009 2:41 am
p=Ks/r, k is a constant
from the condition given
1=K2/.5
or K=1/4

p=s/4r i.e. C
The powers of two are bloody impolite!!

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by shibal » Thu Jul 16, 2009 6:14 am
You could also think like this.... If i know p is 1, s is 2 and r 0.5, how can i manipulate s and r (knowing their value) to obtain 1 (p)? 2/(0.5*4)=1