Two gold pieces of masses $20.15 ext{ g}$ and $20.17 ext{ g}$ are added to a box. What is the diff

Question

Two gold pieces of masses $20.15	ext{ g}$ and $20.17	ext{ g}$ are added to a box. What is the difference in the masses of the pieces to correct significant figures?

Professor PC Thomas Classes · Answer

Difference $= 20.17 - 20.15 = 0.02	ext{ g}$. Since both numbers have two decimal places, the result should have two decimal places. Thus, it is $0.02	ext{ g}$ (which has 1 significant figure).