Answer:
discount percent = 25%
Explanation:
Mia bought a poster that was discounted $5 from an original price of $20
Original price is $20
Discount amount is $5
Let x be the percentage of discount
Discount % is x%
original price times discount percentage is equal to discount amount

multiply both times by 100

Divide both sides by 20
x= 25%
So discount percent = 25%