40/50 as a Decimal 0.8 40/50 = 0.8 = 80% Copy 40/50 = 0.8 = 80%. Simplified: 4/5. Formula Used40 ÷ 50 = 0.8 Frequently Asked Questions What is 40/50 as a decimal?0.8.What is 40/50 as a percentage?80%.