20/50 as a Decimal 0.4 20/50 = 0.4 = 40% Copy 20/50 = 0.4 = 40%. Simplified: 2/5. Formula Used20 ÷ 50 = 0.4 Frequently Asked Questions What is 20/50 as a decimal?0.4.What is 20/50 as a percentage?40%.