soy meal is 16% protein ; cornmeal is 8% protein. how many pounds of each should be mixed together to get 320-LB mixture that is 15% protein? any idea on how to solve this i hate percents -_-
Let x = amount of soy meal to be mixed. 16% of this amount is protein, or 0.16x.
Let y = amount of corn meal to be mixed. 8% of this amount is protein, or 0.08y.
The total mixture is 320 lb. The first equation represents the amounts mixed overall:
$\displaystyle x + y = 320$
The total mixture is 15% protein, or 0.15(320) = 48. The second equation represents the amount of protein:
$\displaystyle 0.16x + 0.08y = 48$
So here we have a system of equations:
$\displaystyle x + y = 320$
$\displaystyle 0.16x + 0.08y = 48$
Solve for x and y.
EDIT: Typos.