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Need helppp

by sohaib_iba » Wed Jun 02, 2010 12:48 am
In an election 4% of the votes cast are invalid. A candidate gets 55% of the valid votes and wins the election by 240 valid votes. Find the total number of votes cast?

A) 2500
B) 2000
C) 1250
D) 3500
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by Rahul@gurome » Wed Jun 02, 2010 1:14 am
The candidate gets 55% of valid votes.
So the other candidates get (100-55)% or 45% of valid votes.
The candidate wins by (55-45)% or 10% of valid votes.
Now 10% of valid votes is 240.
So total no. of valid votes is 240/(10%) which is 2400.
Also 4% of total votes is invalid.
So (100-4)% or 96% of total votes is valid.
So 96% of total votes is 2400.
So total number of votes is 2400/(96%) = 2500.
The correct answer is (A).
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by selango » Wed Jun 02, 2010 2:27 am
Let the number of votes cast be x.

Valid votes =96/100*x=y

Winning candidate gets 55% of valid votes and wins the election by 240 votes-->

The other candidate gets 45% of votes.

-->55/100*y=45/100*y+240

y=2400

96/100*x=2400

x=2500

option A

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by gmatjedi » Wed Jun 02, 2010 3:48 am
0.96*x*0.55=0.96*x*0.45+240

x= 2500