Question 338998
Call the number of plastic cups p.

500 cups were sold in total, so that means that 500-p ceramic cups were sold.

A discount store sold plastic cups for $3.25 each -at a cost of 3.25p-and ceramic cups for $4.50 each -at a cost of 4.5*(500-p)....for a total of 2,090

So

3.25p + 4.5(500-p) = 2090

Now we can just solve for p....


3.25p + 2250 -4.5p = 2090
2250-2090 = 4.5p-3.25p
160 = 1.25p
p = 160/1.25 = 128

128 plastic cups were sold for 128*3.25 = $416

500-128 = 372 ceramic cups were sold for 372 *4.5= $1674

Check: 416+1674 = 2090