You spend $30.40 on 4 CDs. Each CD costs the same amount and is on sale for 80% of the original price.

Answer: The original price is $9.5

In this question, you are given the total spending ($30.40), amount of spend (4CDs) and the discounted price (80%). Then to find the original price of the CD, the calculation would be:

Total spending = amount of cd x CD discounted price

$30.40 = 4 x 0.8 Original price

3.2 Original price = $30.40

Original price = $9.5