Answers:
Hasan's Expression: d - 0.25d
- d: Original price
- 0.25: percent discount
- 0.25d: amount of discount
- d - 0.25d: sale price
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Bella's Expression: 0.75d
- 0.75: percent of original price
- d: original price
- 0.75d: sale price
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Step-by-step explanation:
The variable d stands for the original price. The store is offering a 25% sale, which means that Hasan will save 25% of the original price. This means 0.25d represents the amount he saves (aka the discount amount).
For instance, let's say d = 100 is the original price. 25% of this is 0.25d = 25 dollars. So if the book is originally $100, then he saves $25.
As you can probably guess, the 0.75 comes from 1 - 0.25 = 0.75; it indicates that if Hasan saves 25%, then he still has to pay the remaining 75%
Notice how d - 0.25d = 1d - 0.25d = (1-0.25)d = 0.75d which points to the sale price being 75% of the original price d.