Answer:
Market price $400
Cost price $300
Step-by-step explanation:
MP: market price
CP: cost price
1. (MP x 0.9) - CP = 60
CP = 0.9MP - 60
2. MP - CP = 100
CP = MP - 100
0.9MP - 60 = MP - 100
MP - 0.9MP = 100 - 60
0.1MP = 40
MP = 400
Cost price = MP - 100 = 400 - 100 = 300
