Water is pumped from a cuboidal tank of dimensions 4m×3m×2m to an overhead tank has radius 60cm and height 80cm fond the height of water left in tank

It is 5000cm if the volume of both of them are same

If the cuboidal tank is complete filled with water  ---> volume of water = 4*3*2 = 24  cubic meters.
volume of cylindrical tank = pi*(0.6)^2 (0.8) = 5.0688  cubic meters
volume of water left in cuboidal tank = 24 - 5.0688 = 18.9312  cubic meters.
height of water left in tank = 18.9312 / (area of base)    ....  you must determine dimensions of base.