Question

amy paid $89.21 for a pair of running shoes during a 40% off sale. What was the regular price

Answer 1

89.21/0.6 = 148.68

Answer 2

89.21 is 60% of what number? "is" is "=", "of" is multiply, "what" presumes a variable or unknown aspect. We know that 89.21 is the price paid without 40%. So if we subtract 40% from 100% (the full price of the shoes) we know that the shoes were being sold at 60% of the total price.
89.21=.6n

divide .6 from both sides to isolate the variable and you get 89.21/.6=n
simplify this and you get 148.68(333...)
Exactly, this is $148.68[superscript]1/3 and rounded to the nearest cent it is $148.68