A 1500% discount means the discount is 15 times the original price. For a $500 medicine, a 1500% discount is:
1500% of $500 = 15 × $500 = $7500.
Since this discount exceeds the original price, the cost after discount is: $500 - $7500 = -$7000. A negative cost implies the provider would owe money, which is not practical.
In most real-world scenarios, a discount greater than 100% would result in a price of $0, as you can’t pay less than nothing. Therefore, with a 1500% discount, Grandma would pay: $0 (the medicine is free).