Cashews cost $4 per pound and peanuts cost $1 per pound. How many pounds of peanuts should be used with the cashews to get a mixture of 24 pounds that will cost $2 per pound?
16
9
12.5
6

Question

Cashews cost $4 per pound and peanuts cost $1 per pound.  How many pounds of peanuts should be used with the cashews to get a mixture of 24 pounds that will cost $2 per pound?  
    16  
   9  
   12.5  
   6

anonymous · Answer

16

anonymous · Answer

Assume x pounds of peanuts for x dollars so
24-x pounds of cashews for 4(24-x) then

x + 4(24-x) = 48 (cost of mix)

3x = 48 -> x = 16

amistre64 · Answer

while substitution is the usual route, elimination can be simpler to process for some.

  c +  p = 24       ; *-4
4c +1p = 2(24)


-4c - 4p = -96
  4c +1p =   48
--------------
       -3p = -48    ; solve for p

            p = 48/3 = 16