There was twice as much water in container B as container A at first. Then 1/6 of the water in container B is poured into Container A. There 1.8 liters more water in container B than container A. What was the amount of water in container B at first?

Let be B = how much water is in container B;

A = how much water is in container A;

B = 2A;

B - (1 / 6) B = A + (1 / 6) B + 1.8;

Then, 2A - (2A) / 6 = A + (2A) / 6 + 18 / 10;

2A - A / 3 = A + A / 3 + 9 / 5;

30A / 15 - 5A / 15 = 15A / 15 + 5A / 15 + 27 / 15;

30A - 5A = 15A + 5A + 27;

25A = 20A + 27;

5A = 27;

A = 27 / 5;

A = 5.4 liters;

B = 2 * 5.4 = 10.8 liters;