What is 3% of 40? 1.2 3% of 40 Copy 3% of 40 = 1.2. Formula UsedResult = (3 ÷ 100) × 40 = 1.2 Frequently Asked Questions What is 3% of 40?1.2. (3 ÷ 100) × 40 = 1.2.How to calculate 3%?Multiply by 0.03 (or multiply by 3 then divide by 100).