Concept:

Bulk density of cement = 1440 kg/m3

1 bag of cement = 50 kg

∴ Cement bags required=Volumeofcement×144050

Wet Qty. of concrete = Area × thickness

Dry vol. of concrete = Conversion factor× Wet volume of concrete

Calculation:

Given data

The thickness of floor = 4 cm

Area floor =100 m2

The proportion of M15 grade is1 : 2: 4

Conversion factor = 1.64

Now, Wet Qty. of concrete

= Area × thickness

= 100 sqm × 0.04m= 4.00 cum

So, the dry volume of concrete,

Dry vol. of concrete

=Conversion factor× Wet volume of concrete

= 4.00 cum × 1.64 = 6.56 cum.

Hence, Cement Qty.

= Dry volume of concrete/ (Sum of the ratio values)

= 6.56/ (1 + 2 + 4) = 0.937 cum

Hence, the required amount of cement is0.94 m3