posted by Anonymous .
Suppose we want to charge a flask with 1.9 g of sugar. We put the empty flask on a balance and it is determined to weigh 170 g. Enter the weight we would expect to see on the balance when we're done adding the sugar.
How about 170 + 1.9 = ?
If you are into significant figures, that would be 172 if the mass you were given is 170 and not 170.0 g.