DERIVATION IN CFT
#/ 1 bag of cement=1•226 cft or cubic feet
     Density of cement=1440 kg/m3
We know that, 1 bag of cement=50kg
                  For 1m3, cement required=1440/50=28•8 bags.---------------(1)
Therefore we know that,
                   1m3=35•3147 CFT----------------(2)
  From (1) & (2) we get
   28•8 bags=35•3147 CFT
   1 bag=35•3147/28•8=1•226 CFT.