Question 165550
Soybean meal is 12% protein; cornmeal is 6% protein. How many pounds of each
 should be mixed together in order to get 240-lb mixture that is 10% protein?
How many pounds of cornmeal should be in the mixture?
How many pounds of soybean meal should be in the mixture?
:
Let x = amt (in lb) of Soy meal required
:
It states the resulting mixture will = 240 lb, therefore:
(240-x) = amt to Corn meal required
:
Simple equation using decimal equiv:
.12x + .06(240-x) = .10(240)
:
.12x + 14.4 - .06x = 24
:
.12x - .06x = 24 - 14.4
:
.06x = 9.6
x = {{{9.6/.06}}}
x = 160 lb of Soy
and
240 - 160 = 80 lb of corn
:
:
Check solution:
.12(160) + .06(80) = .10(240)
19.2 + 4.8 = 24; confirms our solution 
:
Pretty easy, right?