GMAT Prep

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Junior | Next Rank: 30 Posts
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GMAT Prep

by KL08 » Sun Sep 23, 2007 7:57 am
Three grades of milk are 1 %, 2% & 3% fat by volume. If x gallons of the 1% grade, y gallons of the 2% grade & z gallons of 3% grade are mixed to give x+y+z gallons of a 1.5 % grade, what is x in terms of y & z?

A) y +3z
B) (y+z)/4
C) 2y+3z
D) 3y+z
E) 3y+4.5z


OA is A

Junior | Next Rank: 30 Posts
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Joined: Sun Aug 26, 2007 11:45 am

by cindyqtran » Sun Sep 23, 2007 8:54 am
hi.

.01x + .02y + .03z = 0.15(x+y+z)
x + 2y + 3z = 1.5(x + y+ z)
.5y + .15z = .5x
5y + 15z = 5x

x = y + 3z

Junior | Next Rank: 30 Posts
Posts: 27
Joined: Sun Aug 12, 2007 7:46 am

by KL08 » Sun Sep 23, 2007 9:10 am
thanx.