In order to calculate how many bags of cement required in 1m3, you should know about the dry density of cement.
In general Density = Mass/Volume
Dry Density of cement = Dry Mass/ Unit Volume
Got confused? Let me explain: In general cement consists of moisture content so Mass of cement includes Cement with Moisture content
Dry Mass includes cement without moisture content
So, Usually, 4% of moisture content is present in cement.
Dry Density of Cement = 1440kg/m3
Each bag of cement consists of = 50kg
No. of bags in 1m3 = 1440/50
= 29bags (approx)
Approximately 29 bags are required for 1m3 of cement.