Question

A cornmeal is 20% protein, and a feed supplement is 60% protein. How much of each must be combined to get 3600 pounds of feed that is 30% protein?

Answer 1

Total amount of protein required = 3600 pounds x 30% = 3600 pounds x 0.3 = 1080 pounds.
Let's call the amount of cornmeal "c" and the amount of supplement "s".
The total weight is 3600, so c + s = 3600.
The amount of protein in cornmeal is 20% x c = 0.2c
The amount of protein in supplement is 60% x s = 0.6s
It needs to total 1080, so 0.2c + 0.6s = 1080.
So we've got two simultaneous equations:
[1] c + s = 3600
[2] 0.2c + 0.6s = 1080
Multiply equation [2] by 5:
[3] c + 3s = 5400
Now subtract equation [1] from equation [3]:
[4] 2s = 1800
So s = 900

Now award best response of medal!!!

Answer 2

No Medal? All you have to do is plug in s and work it out for C

Answer 3

So then it goes c + 3(900) = 5400
c+2700=5400
c=2700
Does that look right?

Answer 4

Yes it is right

Answer 5

Oh okay well thank you!