What is 9% of 80? 7.2 9% of 80 Copy 9% of 80 = 7.2. Formula UsedResult = (9 ÷ 100) × 80 = 7.2 Frequently Asked Questions What is 9% of 80?7.2. (9 ÷ 100) × 80 = 7.2.How to calculate 9%?Multiply by 0.09 (or multiply by 9 then divide by 100).