The concrete volume required for pouring the water tank is equal to the cuboid volume with the length, width and height of 10dm, 6dm and 5dm respectively minus the cuboid volume with the length, width and height of 8dm, 4dm and 5dm respectively.

Answer:

10x6x5-(10-1x2) x (6-1x2) x5 = 300-160 =140 (cubic decimeter).

Or: [1×/kloc-0 /× 2+(6-/kloc-0 /× 2 )×/kloc-0 /× 2 ]× 5 =140 (cubic decimeter).

Or: [(10-1× 2 )×/kloc-0 /× 2+6×/kloc-0 /× 2 ]× 5 =140 (cubic decimeter) ... This is calculated by multiplying the bottom area by the height, and analyzed.

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