The sale price of an item of $60.00. This is after a 15% discount. What was the original cost of the item?

First, you put 15 over 100 then put P over 60 next to that. Next, you multiply 15 by 60 and get 900. Now you divide that by 100 and get 9.00. Finally, you add the 9 60 because it was a discount and get 69. The original cost is $69.

X * (1 - 15/100) = 60

.85x = 60

x = 70.59