Question

a mixture of 40 litters of wine and water contains wine and water in the ratio 3:1. How much water added to it so that the ratio of wine to water may 5:2​

Answer 1

$3x + x = 40 \\ x = 10 \\ wine = 3 \times10 \\ = 30 \\ water = 10 \times 1 \\ = 10 \\ suppose \: ratio \: of \: wine \: water = 5 \div 2 \\ then \: 30 \div 5 = 6 \\ now2 \times 6 = 12 \\ water = 12litres$