Answer:
His rate of discount=10%
Explanation:
Step 1: Get the discount amount
Discount amount=List price-sale price
where;
List price=$800
Sale price=$720
replacing;
Discount amount=(800-720)=80
Discount amount=$80
Step 2: Calculate discount rate
The discount rate can be calculated as;
discount rate=(discount/List price)×100
where;
discount=$80
List price=$800
replacing;
discount rate=(80/800)×100=10%
discount rate=10%