A contractor combined x tons of gravel mix that contained 10% gravel G by weight, with y tons of a mixture that contained 2% gravel G by weight to produce z tons of a mixture that was 5% gravel G by weight. What is the value of x?
1) y = 10
2) z = 16
OA: D
I do not understand how the OA is correct ...
% Mixture Problem
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Guys, master this type of problems. Learn allegation rule found in books.google.com. Allegation rule is a figurative way of solving algebraically.
Sort the mixtures: 2 and 10
2 ------- 10
------5-----
(10-5) : (5-2) = 5:3
-----------------------------------------------------------------------
Mixture of 2% and 10% = 5%
The ratio of quantities gotta be: 5:3 = y : x
x+y = z
(1) y = 10; x = 6 Sufficient
(2) z = 16; x = 3(2) = 6 Sufficient
Sort the mixtures: 2 and 10
2 ------- 10
------5-----
(10-5) : (5-2) = 5:3
-----------------------------------------------------------------------
Mixture of 2% and 10% = 5%
The ratio of quantities gotta be: 5:3 = y : x
x+y = z
(1) y = 10; x = 6 Sufficient
(2) z = 16; x = 3(2) = 6 Sufficient
A link would be cool. I can't seem to find what you are referring to.palvarez wrote:Guys, master this type of problems. Learn allegation rule found in books.google.com. Allegation rule is a figurative way of solving algebraically.
Thanks for the help though.
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- Master | Next Rank: 500 Posts
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Don't waste your money on buying books. Think of that problem as a weight balance problem in physics: another way of loking at the issue.
Average is equilibrium.
Weight*length = constant
w1*l1 = w2*l2
l1 = 5 -2 =3
l2 = 10 -5 = 5
3*y = 5*x
x: y = 3:5
Alligation rule is used heavily in pharmacy classes. Esp it is handy when one is dealing with a mixture of three components, etc.
Average is equilibrium.
Weight*length = constant
w1*l1 = w2*l2
l1 = 5 -2 =3
l2 = 10 -5 = 5
3*y = 5*x
x: y = 3:5
Alligation rule is used heavily in pharmacy classes. Esp it is handy when one is dealing with a mixture of three components, etc.