Question

Marjorie went shopping on Black Friday and received successive discounts of 25%, 40% and 20% off the original price. If Marjorie wanted to purchase the same items this week, what single percent discount would she have to receive off the original prices to get the items for the same price that they were on Black Friday after the three successive discounts?

Answer 1

64% single discount!

Explanation:

1. Convert each to a decimal first.

25% to 0.25

40% to 0.4

20% to 0.2

2. Subtract each decimal by 1

1 - 0.25 = 0.75

1 - 0.4 = 0.6

1 - 0.2 = 0.8

3. Multiply all

0.75*0.6*0.8 = 0.36

4. Subtract this decimal by 1

1 - 0.36 = 0.64

5. Convert back to percentage

0.64 * 100 = 64 or 64%

Answer 2

Given that Marjorie received successive discounts of 25%, 40% and 20% off the original price, on Black Friday.

If Marjorie wanted to purchase the same items this week, the single percent discount she would have to receive off the original prices to get the items for the same price that they were on Black Friday after the three successive discounts is given by

1 - Single Discount = (1 - 0.25)(1 - 0.40)(1 - 0.20) = 0.75 x 0.60 x 0.80 = 0.36

Therefore, single discount = 1 - 0.36 = 0.64 = 64%.