krishnasty wrote:IMO A

Here's my approach :

From the statement, we can infer that
10%x + 2%y = 5%z => .1x + .02y = .5z

but, also, from the mixture, x+y = z
hence, the equation becomes,
.1x +.02y = .5(x+y)...we need values of x or y to get the other variable.

(A) gives values of y. Hence, we can find out the value of X..sufficient
(B) gives value of z..whcih is value of x+y..hence, insufficient.

My ans : A

pemdas wrote:you say 10%x + 2%y = 5%z then you say 100%x + 100%y = 100%z ?

krishnasty wrote:IMO A

Here's my approach :

From the statement, we can infer that
10%x + 2%y = 5%z => .1x + .02y = .5z

but, also, from the mixture, x+y = z
hence, the equation becomes,
.1x +.02y = .5(x+y)...we need values of x or y to get the other variable.

(A) gives values of y. Hence, we can find out the value of X..sufficient
(B) gives value of z..whcih is value of x+y..hence, insufficient.

My ans : A

A contractor combined x tons of a gravel mixture 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