Question

ONLY ANSWER IF YOU ACTUALLY KNOW THE ANSWER, AND IS ABLE TO EXPLAIN EVERYTHING

Cait purchased a $20 item at a store. She uses a coupon to receive a 15% discount, and she pays a 6% sales tax on item. She calculates the total cost, in dollars, of the item using the expression:

(1.15)(1.06)(20)

A. Describe the error in the expression Cait used for her calculations.


B. Show or explain how you would calculate the total cost of Cait's purchase.

Answer 1

A. Describe the error in the expression Cait used for her calculations.
For this case we have:
She uses a coupon to receive a 15% discount:
(100-15) * (1/100) = 0.85
she pays to 6% sales tax on item:
(100 + 6) * (1/100) = 1.06
Therefore, the error is given by:
(1.15) (1.06) (20)
the term 1.15

B. Show or explain how you would calculate the total cost of Cait's purchase.

The total cost for this case is given by the following expression:
(0.85) (1.06) (20)
Calculating we have:
$ 18.02