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.
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.