The ratio of spirit and water in two mixtures of 20 litres and 36 litres is 3:7 and 7:5 respectively. Both the mixtures are mixed together. Now the ratio of the spirit and water in the new mixture is 

In an alloy, zinc and copper are in the ratio 1 : 2. In the second alloy the same elements are in the ratio 2 : 3. In what ratio should these two alloys be mixed to form a new alloy in which the two elements are in ratio 5 : 8?

Two vessels A and B contains acid and water in the ratio 4:3 and 5:3 respectively Then the ratio in which these mixtures to be mixed to obtain a new mixture in vessel C containing acid and water in the ratio 3:2 is