Eric purchased three cd’s and sweatshirts and received a 20% discount, he paid $100. the following week the same store offered 40% off everything, his friend bought 4 cd’s and 2 sweatshirts for $120.

assuming the prices were unchanged cd’s cost:
and sweatshirts cost:

The CDs cost $25 and sweatshirt cost $50.

Step-by-step explanation:

Eric purchased 3 CD's and a sweatshirt for $100 after getting a discount of 20%. That means the original price of the items were $125.

Here we will get two equations and we have to solve these two equations to get the value of the commodities.

Lets represent CDs by x and sweatshirts by y.Then,

3x + y = 125      (1)

Then his friend his bought 4 CDs and 2 sweatshirts at $120 after 40% discount. Hence the original price is $200.

This is shown by,

4x + 2y = 200     (2)

We have to solve these both equations.

x = 25

y= 50

The CDs cost $25 and sweatshirt cost $50.