10/25 as a Decimal 0.4 10/25 = 0.4 = 40% Copy 10/25 = 0.4 = 40%. Simplified: 2/5. Formula Used10 ÷ 25 = 0.4 Frequently Asked Questions What is 10/25 as a decimal?0.4.What is 10/25 as a percentage?40%.