In What proportion must flour at $0.8 per pound be mixed with flour at $0.9 per pound so that the mixture costs $0.865 per pound? Select:
A) 1:3
B) 1:2
C) 1:1
D) 2:1
E) 3:1
Using weighted average method:   Let x be the proportion in which the $0.8 per pound flour is mixed with $0.9 per pound flour.   Thus 0.8*x + 0.9*(1-x) = 0.865   0.9 – 0.1x = 0.865   x = 0.35   Thus ratio of both flours is 1:2   1:2
<result>B</result>
In What proportion must flour at $0.8 per pound be mixed with flour at $0.9 per pound so that the mixture costs $0.865 per pound?