using reaction 4Al+3O2=4Al2O3,identify limiting reactant with 78.2gAl and 113.1g of O2?

Question

my stoichiometry problem,i have really crazy calculations and was wondering if they are right
i got 2364.20 O2 and 2162.18 Al so Al is limiting reactant
but i doubt its right

i am in 11 grade chemistry and almost failing with a C

Answer 1

Moles of Al= 78.2/26.98=2.9
moles of O2 = 113.1/32 =3.5
Now 4 : 3 = 2.9 : x
x=2.17 moles of O2 needed. Since we have 3.5 moles of O2 (1.3 about in excess) the limiting reactant is Al

Answer 2

Have no idea but out of interest what grade are you in and what are you majoring in? The above seems scary to me haha. So I was wondering when I will come in contact with it.