Amy paid $65.78 for a pair of running shoes during a 40 %-off sale. What was the regular price?

This problem can be represented by the following:

sale price = (percentage off) * original price

Plug in the values given by the problem. 60% is represented in this equation as 0.6.

65.78 = 0.6x

Divide both sides by 0.6.

109.63 = x

The original price was $109.63.