Option E: There are a number of ways to calculate percentages. The common way of doing it is: 12.8% of 715 = $$frac{12.8}{100}$$ $$ imes 715 $$ = $$frac{9152}{100}$$ = 91.52 Alternatively, we can also do it in parts. 12.8% of 715 is same as 10% of 715 + 2% of 715 + 0.8% of 715 i.e. 71.5 + 14.3 (=1/5th of 10%) + 5.72 (=4/5th of 1%) which gives 91.52