Raphael paid $648 for a camera during a 20% off sale. what was the camera's regular price?

100% - 20% = 80%

Solution 1:

100% = x

80% = $648

80x = 64800

x = $810

Solution 2:

80% • x = $648

80/100 • x = 648

80x = 64800

x = $810

Check:

20% * $810

= 20/100 * $810

= $648

The camera's regular price is $810.