What is 90% of 10? 9 90% of 10 Copy 90% of 10 = 9. Formula UsedResult = (90 ÷ 100) × 10 = 9 Frequently Asked Questions What is 90% of 10?9. (90 ÷ 100) × 10 = 9.How to calculate 90%?Multiply by 0.9 (or multiply by 90 then divide by 100).