Given #Fe_2O_3(s) + 3CO(g) rarr 2Fe(s) + 3CO_2(g)#, how do we calculate the molar equivalence?
You have a stoichiometrically balanced equation, and a molar quantity of ferric oxide.
And thus 1 equiv ferric oxide reacts with 3 equiv carbon monoxide to give 2 equiv iron, and 3 equiv carbon dioxide.
All of these answers are pretty straightforward, and do not even require a calculator. Writing the stoichiometric equation, so we can see the equivalence, is absolutely vital.