SOLUTION: Soybean is 18% protein Cornmeal is 9% protein How many lbs of each should be mixed together to get 360-lb mixture that is 12% protein?

Algebra.Com
Question 436332: Soybean is 18% protein
Cornmeal is 9% protein
How many lbs of each should be mixed together to get 360-lb mixture that is 12% protein?

Found 3 solutions by stanbon, htmentor, josmiceli:
Answer by stanbon(75887)   (Show Source): You can put this solution on YOUR website!
Soybean is 18% protein
Cornmeal is 9% protein
How many lbs of each should be mixed together to get 360-lb mixture that is 12% protein?
----
Equations:
Quantity Eq: s + c = 360 lb
Protein Eq:0.18s+0.09c = 0.12(360)
---------------------------------------
Multiply thru the 1st by 18
Multiply thru the 2nd by 100
--------------------------------
18s + 18c = 18*360
18x + 9c = 12*360
----------------------
Subtract and solve for "c":
9c = 6*360
c = (2/3)360
c = 240 lb. (amt. of cornmeal needed)
===============
Solve for "s":
s + c = 360
s + 240 = 360
s = 120 lb (amt of soybean needed)
======================================
Cheers,
Stan H.
===============

Answer by htmentor(1343)   (Show Source): You can put this solution on YOUR website!
Let x = the number of pounds of soybeans
Then 360-x = the number of pounds of cornmeal
A 360 lb. 12% mixture contains 0.12*360 = 43.2 lb
So we can write the following equation:
0.18x + 0.09(360-x) = 43.2
Solve for x:
0.09x = 43.2 - 32.4 = 10.8 -> x = 120
So the number of lbs of soybeans = 120
And the number of lbs of cornmeal = 360-120 = 240

Answer by josmiceli(19441)   (Show Source): You can put this solution on YOUR website!
Let = pounds of soybean needed
Let = pounds of cornmeal needed
given:
= protein in soybeans
= protein in cornmeal
(1)
(2)
-----------------------
(2)
(2)
(2)
(2)
Multiply both sides of (1) by and
subtract (1) from (2)
(2)
(1)


and
(1)

120 pounds of soybeans are needed
240 pounds of cornmeal are needed
check answer:
(2)
(2)
(2)


OK

RELATED QUESTIONS

soybean meal is 18% protein, cornmeal is 9% protein. How many pounds of each should be... (answered by robertb)
soybean meal is 18% protein cornmeal is 9% how many pounds of each should be mixed... (answered by stanbon)
soybean meal is 18% protein; cornmeal is 9%. How many pounds of each should be mixed... (answered by scott8148)
Soybean meal is 18% protein; cornmeal is 9% protein. How many pounds of each should be... (answered by josgarithmetic)
Soybean meal is 18% protein; cornmeal is 9% protein. How many pounds of each should be... (answered by mananth)
soybean meal is 18% protein,cornmeal is 9% protein.How many pounds of each should be... (answered by josmiceli)
Soybean meal is 18%protein; cornmeal is 9% protein. How many pounds of each should be... (answered by John10)
soybean meal is 18% protein; cornmeal is 9% protein. How many pounds of each should be... (answered by checkley77)
Soybean meal is 18% protein; cornmeal is 9% protein. How many pounds of each should be... (answered by checkley77)