"Carbon combines with 4/3 times its mass of oxygen."

Please explain this statement .

Dear Student,
Mass of 1 atom of carbon = 12 u
Mass of 1 atom of oxygen = 16 u
         2C + O₂  ------------->  2CO 
1 molecule of carbon monoxide contains 1 atom of carbon and 1 atom oxygen
So, the mass of 1 molecule of CO = 12 + 16 = 28 u,
in which the mass of C and O are present in the ratio of 12 : 16.
Simply 12 : 16, we get 3 : 4.
This shows that Carbon combines with 4/3 times its mass of oxygen to form carbon monoxide.
Regards