Answer:
The discount is $0.8d.
Step-by-step explanation:
Given that,
The original cost of Tamara's purchase is d dollars.
Tamara uses a coupon to save 20% off her purchase at the bookstore.
Discount = 20%
Discount is applied to the original cost.
Discount = d-(20/100)d
Discount = 0.8 d
Hence, the discount is $0.8d.
