Answer:
a. $16.90
b. 23.5%
Step-by-step explanation:
a. After the two discounts, the original price is multiplied by ...
(1 -10%)(1 -15%) = 0.90×0.85 = 0.765
Then the original price is found from ...
$12.93 = 0.765 × original price
original price = $12.93 / 0.765 ≈ $16.90
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b. The effective discount from the original price is ...
1 -0.765 = 0.235 = 23.5%