Let's say p is the principal cost of the total (original) we can setup the equation p-.4p=40.5 => .6p=40.5 => p=67.5
So the cost without the sale is $67.50
For the original price of each pair divide this by 3.
67.5/3=22.5
Final answer:
Each pair costs $22.50 without the sale.
Hope I helped :)
