Jack bought 3 slices of cheese pizza and 4 sclices of mushroom pizza for $12.50. Grace bought 3 slices of cheese pizza and 2 slices of mushroom pizza for $8.50. What is the cost of 1 slice of mushroom pizza?
A) $1.50 B) $2.00 C)$3.00 D)$3.50

Question

Jack bought 3 slices of cheese pizza and 4 sclices of mushroom pizza for $12.50. Grace bought 3 slices of cheese pizza and 2 slices of mushroom pizza for $8.50. What is the cost of 1 slice of mushroom pizza?
A) $1.50  B) $2.00  C)$3.00  D)$3.50

anonymous · Answer

In this case, c=cheese pizza and m=mushroom pizza. (:

For Jack: 3c+4m=12.50
For Grace: 3c+2m=8.50

Subtract the two equations above:
   3c+4m=12.50
-(3c+2m=8.50)
_________________
          2m=4
            m=2
Answer is B) $2.00