A pool is 50m long and 20m wide. it is 1.2m deep at the shallow end and 2.5m deep on the deeper end?

Question

how many cubic meters of water can it hold if it is filled so that the surface of the water is 2 dm from the edge of the pool?

Answer 1

volume of cuboid=50 x 20 x 2.5 = 2500 cubic m

volume of remaining region= [1/2]x 50 x 1.3 x 20= 650 cubic m

So, the volume of the pool=2500-650= 1850 cubic m

Answer 2

The average depth of the pool is 1.85m. Take away 0.2m (2dm) from this because the water is not to fill the pool. Then calculate the volume:

V = 1.65 x 20 x 50.