Mixture problem, whats the best approach?? GMAT Prep

[blitz28]

Three Grades of milk are 1%, 2% and 3% fat by volume. If x gallons of 1 % grade, Y gallons of 2% and Z gallons of 3% grade are mixed to X+Y+Z galllons of 1.5 % grade. What is X in terms of Y and Z

a) y+3z

b)(Y+Z)/4

c)2Y+3Z

d)3Y+Z

e)3Y+4.5 Z

Solutions???

[blitz28]

Thanks Guys,

Got it the moment I posted...

Guess BTG is magic mantra )

[hrishikesh05]

Well the answer is A

[Uri]

Thanks Guys,

Got it the moment I posted...

Guess BTG is magic mantra )

What is "BTG" :

[blitz28]

BTG is where u r operating

Beat the GMAT!!!

[mdavis]

Would someone mind posting a solution? Thanks!

[Stuart@KaplanGMAT]

Three Grades of milk are 1%, 2% and 3% fat by volume. If x gallons of 1 % grade, Y gallons of 2% and Z gallons of 3% grade are mixed to X+Y+Z galllons of 1.5 % grade. What is X in terms of Y and Z

a) y+3z

b)(Y+Z)/4

c)2Y+3Z

d)3Y+Z

e)3Y+4.5 Z

Solutions???

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

multiply by 200 to clear decimals:

2x + 4y + 6z = 3(x+y+z)
2x + 4y + 6z = 3x + 3y + 3z

separate the "x"s from the "y"s and "z"s:

y + 3z = x

choose (A)!