# RE2 | perplexity/sonar-pro | run 2

## Prompt

After a 20% discount, a jacket costs $40. What was the original price? Show your work.

## Response

After a **20% discount**, the sale price is **80%** of the original price, so the original price is \(40 \div 0.8 = 50\). The jacket originally cost **$50**.[6]

**Work:**
- Original price \(= \dfrac{\text{sale price}}{1 - \text{discount rate}}\)
- Original price \(= \dfrac{40}{1 - 0.20}\)
- Original price \(= \dfrac{40}{0.80} = 50\)[6]

Would you like me to show a quick mental-math shortcut for these discount problems?
