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by EMAN » Sat Oct 17, 2009 12:50 pm
Last year, all registered voters in Kumania voted either for the Revolutionary Party or the Status Quo Party. This year, the number of Revolutionary voters increased 10%, while the number of Status Quo voters increased 5%. No other votes were cast. If the number of total voters increased 8%, what fraction of voters voted Revolutionary this year?
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by truplayer256 » Sat Oct 17, 2009 1:08 pm
Let's assume that of the registered voters in Kumania, x voted for the Revolutionary party while y voted for the Status QUO party. If this is the case, then this year there were:

1.10x Revolutionary voters and 1.05y Status QUO voters. If the total number of voters this year was an 8% from last year's, then:

1.08(x+y)=1.10x+1.05y

3y=2x

We're looking for 1.10x/1.10x+1.05y. Substitute x=3/2y into the expression to get:

1.10(3/2y)=33/20y

33/20y/(33/20y+21/20y)=33/20y/(54/20y)=33/54=11/18.
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!

by EMAN » Sun Oct 18, 2009 1:26 pm
Man, you are a true playa. Your strategy is very helpful and straightforward. Thank you for the response.
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