Percentage discounts

Further examples of percentage discounts with access to a calculator

Question 2

Zoe bought a bike helmet at the discounted price of $55. If the discount was 20% what was the original price?

Solution

1 − 20% = 1 − \(\dfrac{20}{100}\) = 1 − 0.2 = 0.8.

Method 1

80% of the price is $55.

10% of the price = $\(\dfrac{55}{8}\) = $6.875.

100% of the price = $68.75.

Method 2

Let $x be the price of the helmet before discounting. The price of the helmet before discounting was $68.75.

0.8 × x = 55

x = \(\dfrac{55}{0.8}\)(Divide by 0.8.)

= 68.75.

The price of the helmet before discounting was $55.

Solution to question 1 continued

Questions 3, 4, and 5