SOLUTION: How many pounds of nuts selling for $6 per lb and raisins selling for $3 per lb should a person combine to obtain 90lb of trail mix selling for $4 per lb?

Question 953265: How many pounds of nuts selling for $6 per lb and raisins selling for $3 per lb should a person combine to obtain 90lb of trail mix selling for $4 per lb?
Found 2 solutions by stanbon, josgarithmetic:
Answer by stanbon(75887) (Show Source): You can put this solution on YOUR website!
How many pounds of nuts selling for $6 per lb and raisins selling for $3 per lb should a person combine to obtain 90lb of trail mix selling for $4 per lb?
---------------
Quantity:: n + r = 90 lbs
Value:::: 6n +3r = 4*90 dollars
------------------------------------
Modify for elimination::
3n + 3r = 3*90
6n + 3r = 4*90
--------------------------
Subtract and solve for "n":
3n = 90
n = 30 lbs (wt. of $6 nuts needed)
-----
Solve for "r"::
r = 90-n
r = 60 lbs (wt. of $3 raisins needed)
====================
Cheers,
Stan H.
-------------
Answer by josgarithmetic(39617) (Show Source): You can put this solution on YOUR website!
n, nuts
r, raisins
n+r=90
n=90-r
OR
n, nuts
90-n, raisins.
That might be simpler.

You know what to do when you understand the equation
RELATED QUESTIONS
How many pounds of nuts selling for $6 per lb and raisins selling for $3... (answered by josmiceli)
How many pounds of nuts selling for $6 per lb and raisins selling for... (answered by josmiceli)
How many pounds of nuts selling for $12 per lb and raisins selling for $6 per lb should a (answered by josmiceli)
How many pounds of nuts selling for $12 per lb and raisins selling for $6 per lb should a (answered by josmiceli)
How many pounds of nuts selling for $18 per lb and raisins selling for $6 per lb should a (answered by stanbon)
How many pounds of nuts selling for $9 per lb and raisins selling for $3... (answered by fractalier)
How many pounds of nuts selling for $9 per lb and raisins selling for $3 per lb should a... (answered by Alan3354)
How many pounds of nuts selling for $12 per lb and raisins selling for $6... (answered by josgarithmetic)
How many pounds of nuts selling for $12 per lb and raisins selling for $6 per lb should a (answered by stanbon)