1 mixture & allegations problem

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1 mixture & allegations problem

by Skywalker » Tue Aug 24, 2010 9:29 am
1) Three grade of milk are 1%, 2% and 3% fat by volume. If x gallons of the 1% grade, y gallons of the 2% grade and z gallons of the 3% grade are mixed to give x+y+z gallons of 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


Can someone let me know how to proceed in these kind of sums. Thanks
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by Gurpinder » Tue Aug 24, 2010 9:58 am
Skywalker wrote:1) Three grade of milk are 1%, 2% and 3% fat by volume. If x gallons of the 1% grade, y gallons of the 2% grade and z gallons of the 3% grade are mixed to give x+y+z gallons of 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


Can someone let me know how to proceed in these kind of sums. Thanks
whats the oa?
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by Skywalker » Tue Aug 24, 2010 10:04 am
Hi, the OA is (A) !
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by Gurpinder » Tue Aug 24, 2010 10:07 am
Skywalker wrote:Hi, the OA is (A) !
Wow, i was way off. I thought this one was more of ratios, so i was going with (c).

But I THINK you are to setup an equation like this one and solve for x by bringing it to one side and keeping the other 2 variables on the other side.:

.01x+.02y+.03z=.015(x+y+z).


experts help!
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by parketizer » Tue Aug 24, 2010 10:48 am
X gallons contains x/100 gallons of fat
Y gallons contains 2Y/100 gallons of fat
Z gallons contains 3Z/100 gallons of fat

X+Y+Z gallons contains (X+2Y+3Z)/100 gallons of fat

Given that fat content is 1.5% of X+Y+Z gallons

Hence 0.015(X+Y+Z) = (X+2Y+3Z)/100

Solving for X gives X= Y+3Z