mixture

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mixture

by rupsk » Tue Aug 16, 2011 8:38 pm
One vessel contains a mixture of 5 parts pure wine and 3 parts soda, whereas the other vessel contains a mixture of 9 parts pure wine and 5 parts soda. Compare the strength of the wine.

A. 35;36
B. 7 : 8
C. 7 : 4
D. 14 : 5
E. None of these
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by edvhou812 » Tue Aug 16, 2011 9:05 pm
I got [spoiler]A, 35/36[/spoiler]

5+3=8
9+5=14
14*8=112

5(14)+3(14)=112
9(8)+5(8)=112
5*14=70
9*8=72
[spoiler]70/72=35/36[/spoiler]

This was just a "shot in the dark." Hopefully my approach was correct.
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by gmatboost » Wed Aug 17, 2011 2:30 pm
Slightly faster approach:

Wine 1 = 5/(5+3) = 5/8 wine
Wine 2 = 9/(9+5) = 9/14 wine

Relative strength:
(5/8) / (9/14) =
(5/8) * (14/9) =
simplify before you multiply!
(5/4) * (7/9) [spoiler]= 35/36[/spoiler]
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by GMATGuruNY » Thu Aug 18, 2011 2:27 am
rupsk wrote:One vessel contains a mixture of 5 parts pure wine and 3 parts soda, whereas the other vessel contains a mixture of 9 parts pure wine and 5 parts soda. Compare the strength of the wine.

A. 35;36
B. 7 : 8
C. 7 : 4
D. 14 : 5
E. None of these
Fraction of wine in the 1st vessel = 5/8.
Fraction of wine in the 2nd vessel = 9/14.

To compare fractions, multiply the numerator in each fraction by the denominator in the other.

1st numerator: 5*14 = 70.
2nd numerator: 9*8 = 72.

Ratio = 70:72 = 35:36.

The correct answer is A.
Last edited by GMATGuruNY on Thu Aug 18, 2011 6:04 am, edited 1 time in total.
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by rupsk » Thu Aug 18, 2011 3:01 am
thanks for reply i got it