A feed store sells two varieties of birdseed: Brand A, which is 40% millet and 60% sunflower, and Brand B, which is 65% millet and 35% safflower. If a customer purchases a mix of the two types of birdseed that is 50% millet, what percent of the mix is Brand B?
Choose the correct choice from the following choices
A) 40%
B) 45%
C) 50 %
D) 60 %
E) 55 %
Yes there is a simple method :   Consider the following method   Brand A : 40% millet and 60% sunflower   Brand B : 65% millet and 35% safflower   Mix : 50% millet   Here the weighted average is 50%,   Now Brand A has 40% millet, which is 10% less than the weighted average of mix = - 0.10 A --------------- I   Similarly, Brand B has 65 % millet, which is 15 % more than the weighted average of mix = + 0.15 B ------------ II   Now, both Brand A and Brand B are combined to give a 50% mix containing millet, so equate I and II   implies, 0.10 A = 0.15 B   Therefore A/B = 0.15/0.10 = 3/2   A : B : (A + B) = 3 : 2 : (3+2) = 3 : 2 : 5   We have to find, percent of the mix is Brand B i.e. B : (40% + B) = 2 : 5 = (2 / 5) * 100= 
<gadget id="calculator">(2 / 5) * 100</gadget>
<output>40</output>
40 %   Here is a pictorial representation :   Brand 40%= 40%------------------------10% or 0.10 below average, 40% times-----------------Total below = - 0.10 40%   ----------------------------------------------------------------------------------------40%verage = 50% or 0.50   Brand B = 65 %--------------------------15% or 0.15 above average, B times-----------------Total above = + 0.15 B   Since the amount below the average has to equal the average above the average; therefore,   0.10 40% = 0.15 B   40%/B = 3/2   40%:B: Total = 3:2:5   Therefore   B/Total = 2:5 = 40 %   40%nswer: 40%
<result>A</result>
A feed store sells two varieties of birdseed: Brand A, which is 40% millet and 60% sunflower, and Brand B, which is 65% millet and 35% safflower. If a customer purchases a mix of the two types of birdseed that is 50% millet, what percent of the mix is Brand B?