3 containers having capacities in the ratio 2: 3: 1 contain mixture of liquids A and B such that the ratio of A to B in them is 2: 3, 1: 4 and 3: 7 respectively. If all the three containers are emptied in a single container, what will be the ratio of A to B in the final mixture?

Let capacities be 2x, 3x, x. Container 1 (capacity 2x) has A:B = 2:3, so A = (2/5)×2x = 4x/5, B = 6x/5. Container 2 (capacity 3x) has A:B = 1:4, so A = (1/5)×3x = 3x/5, B = 12x/5. Container 3 (capacity x) has A:B = 3:7, so A = (3/10)×x = 3x/10, B = 7x/10. Total A = 4x/5 + 3x/5 + 3x/10 = 17x/10. Total B = 6x/5 + 12x/5 + 7x/10 = 43x/10. Ratio A:B = 17:43.