asharma86 wrote:

Hi all,

I am studying from the

Manhattan GMAT books and can't seem to get a grasp on the strategy used for weighted averages problems. An example:

A feed store sells two varieties of birdseed: Brand A, which is 40% millet and 60% sunflower, and Brand B, which is 65% miller and 35% sunflower. If a customer purchases a mix of the two types of birdseed that is 50% miller, what percent of the mix is Brand A? The solution in the book involves making a table. I am wondering if someone knows of another, quicker strategy.

Thanks a lot.

- AS

there are 2 ways to solve it. The first is the traditional algebra where we take .4(A) +.65(B)/(A)+(B)=.5

The other method is from the Mixture Problems Made easy sheet that Im attaching. Its even simpler that way.