Question

A DVD player was priced at $90 and it was sold at a discount of 20%.After the discount, the shop keeper still make a profit of 20%.What is the cost price of the DVD player?
@campbell_st

Answer 1

ok... so the discounted price = 90 - 18
= 72

so allowing for a 20% profit

Cost + 20% = 72

or

1.2*cost = 72

divide both sides of the equation by 1.2 to get the cost price.

Answer 2

I'll get $60

Answer 3

One thing I don't understand is..
why 1.2*cost
@campbell_st

Answer 4

well the 20% profit is based on the cost price....

so the selling price is cost price + 20% of cost price(profit)

Answer 5

Got it

Answer 6

Thank you @campbell_st