You actually wants to calculate the volume in cubic meters.
Volume for this solid, a cobblestone rectangle, is calculated simply multiplying area of the base by its height.
Replacing the given values in the formula, we get
V = ABh = 90 x 405 x 5 cm3
V = 182250 cm3
Now we convert to cubic meters by dividing by 100x100x100 = 100,000.
V = 182250/100,000 = 1.8225 m3 (cubic meters) (answer)
so, you will need approximately 2 m3 of sand cement mix.
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