Question

Penelope is saving up to purchase a new bike that costs R dollars. She has a 10% off coupon. Which expression represents the total cost of the item, in dollars, after the discount has been applied? (choose 2)
Responses
A 0.90R0.90 R
B 0.10R0.10 R
C 1 – 0.10R1 – 0.10 R
D (1 – 0.10)R (1 – 0.10) R
E (1 + 0.10)R(1 + 0.10) R

Answer 1

Answers: A and D.

Reason: A, 0.90R, equals 90% of R (you pay 100% − 10% = 90% of the price). D, (1 − 0.10)R, is the same expression written as a factor.
B is just the discount amount (10% of R), C evaluates to 1 − 0.10R (not 0.90R), and E is a 10% markup (1.10R).