A jacket originally costs $120. It is on sale for 15% off the original price. What is the sale price of the jacket?
A sale labeled “percent off” is a percent decrease from the original price. Start with the full , subtract the discount, then use Desmos’s % of entry to find the remaining share of the original price. The discount is what you save, not what you pay.
Hints
- Hint 1
A discount is the part taken away from the original price. The jacket starts at $120, so what percent remains after 15% is taken away?
- Hint 2
The full original price is . Subtract the 15% removed from that, then find the remaining percent of $120 to get the price you pay.
Step-by-step
Find the percent left after the discount
Step 1Translate “15% off” into a sale-price expression
The $120 is the base, the price the percent is taken of. A 15% discount removes part of that original price, so the sale price is the part left:
- Step 2
Find the percent that remains
Subtract the discount from the full :
So 85% remains of the original price. The 15% is the part removed, not the part you pay.
- Step 3
Calculate the sale price
Type in Desmos. It returns , so the sale price of the jacket is $102. Choice B.