Question

Nicole sold 1 cherry pie and 9 pumpkin pies for $60. Lisa sold 11 cheery pies and 4 pumpkin pies for $90. what's the cost each of one cherry pie and one pumpkin pie?

Answer 1

Cherry pie  is $ C.
Pumpkin pie is $ P.

C +   9P =60 -------> C=60 - 9P
11C+4P = 90  

11(60 - 9P) +4P=90
660 - 99P + 4P = 90
-95P = -570
P =570/95 = 6
P=6
C=60-9*P=60 - 9*6= 60-54=6
C=6

Answer: 1 cherry pie -$6, 1 pumpkin pie - $6.

Check:
11C+4P = 90  , 11*6 +4*6 =90, 66+24=90, 90=90 True