A container with base measuring 60 cm by 40 cm and a height of 25 cm was 4/5 filled with water. Some of the water was removed, causing the water level to fall by 5 cm The remaining water was then poured into a tank and a basin, filling them o their brims. The capacity of the basin was 1/3 that of the tank. If the tank was 18 cm long and 15 cm wide, what was the height of the water in the tank?