Question

Find the Percentage Composition of 0.68g of CaCO3 in 1.3g of antacid tablet.

I think it is 680/1300*=approx. 52%

Answer 1

You're right but I would have done it as (0.68/1.3) = 0.52 = 52%. I'm not being picky, rather, I'm pointing out that if I do it your way I'm doing two operations that are not necessary (multiplying both numerator and denominator by 1000 before dividing) and knowing me that's two more steps I can make a math error. And I will probably do that. :-(