IBPS RRB PO Prelims 21 Aug 2022 Shift 1 Paper

A tanker contains a mixture of alcohol and water in the ratio 4 ∶ 5. 10 liters of mixture is drained due to leakage. To compensate it, the driver mixed 10 liters of pure alcohol then the ratio becomes 2 ∶ 1. Find the initial quantity of alcohol in the container.