math
posted by lisa .
A man sells a nut mixture consisting of 1/3 pecans and 2/3 cashews. Pecans cost 3 times as much as cashews. if a pund of the mixture costs him $0.40, how much did he pay for a pond of cashews? a pound of pecans?

the cost of a pound of pecans is p, so
(2/3)c + (1/3)(3c) = 0.40
5/3 c = .40
c = .24
so, cashes cost $0.24/lb
pecans cost $0.72/lb