an open concrete tank is internally 1m wide, 2m long and 1.5m deep, the concrete being 10cm thick. Calculate the capacity of the tank in litres​

Capacity of tank in litres:

1x2x1.5=3m^3 or 3000 litres

Volume of concrete:

(0.1*1.5*1*2)+(0.1*1.5*2(0.1*2))*2)+(0.1*1.2*2.2)=0.3+0.66+0.264=1.224 m^3 of concrete

(Thickness x Depth x Width excluding the thickness of the wall x Two sides) + (Thickness x Depth x Length including the thickness of the wall on both sides x Two sides) + (Base slab dimensions)

What do you mean by that?