Answer:
(c) $80
Step-by-step explanation:
Each discounted price corresponds to the original price multiplied by a factor related to the discount. For a discount fraction of 'd', the multiplier is (1 -d).
This means you can use any of the lines in the table to find the original price.
5% disount: (1 -5%)·p = $76 . . . . where p is the original price
p = $76/0.95 = $80 . . . . . . . the original price
10% discount: (1 -10%)·p = $72
p = $72/0.90 = $80
25% discount: (1 -25%)·p = $60
p = $60/0.75 = $80
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Additional comment
The table values for 5% and 10% differ by 5% and $4. That means 5% of the original price is $4. There are two things you can do with this:
- add back that 5% to the 5%-discounted price: $76 +4 = $80
- multiply that 5% by 20 to get 100% of the original price: 20(5%) = 20($4) ⇒ 100% = $80.
