Methylation of 10g of benzene gives 9.2g of toluene. Calculate the percentage yield of toluene _______ . (Nearest integer)

78g benzene gives 92g Toluene 
1g of benzene gives 1.17g Toluene 
10g with 100% yield gives 11.79g toluene
But experimentally obtained 9.2g.
So % yield $=\frac{9.2}{11.79}\times 100=78\mathrm{\%}$