11Finding original price before discount

After a 20% discount, a game costs $36. What was the price before the discount?

The game cost $45 before the discount. Since $36 is what's left after taking off 20%, it's 80% of the original: 36 ÷ 0.8 = 45. Check: 20% of 45 is 9, and 45 − 9 = 36.