Question 872001
A landscaper wants to use a fertilizer blend that is 8% nitrogen.
 He will mix a 10% nitrogen fertilizer with a 5% nitrogen fertilizer to get 150 lbs. of the 8% blend.
 How many pounds of each type should be mixed to get the desired solution?
:
let x = amt of 10% fert
then because the total is to be 150 lb:
(150-x) = amt of 5% fert
:
.10x + .05(150-x) = .08(150)
.10x + 7.5 - .05x = 12
.10x - .05x = 12 - 7.5
 .05x = 4.5
x = 4.5/.05
x = 90 lb of 10% fert
and
150-90 = 60 lb of 5% fert