They're not important when solving math problems in class because you need to get the correct and accurate answers hence don't need to change them into significant figures
Methane Volume : O.O
Methane Mass: 0.100g
Molar Mass of Methane : 16.04 g/mol
In this problem Al metal is a limiting reactant as it is present in less amount as compared to chlorine gas, Hence, controls the formation of ALCl3. So, the amount of AlCl3 produced is 40.05 grams. Solution is as follow,