CHEMISTRY COMMUNITY

Can someone explain how to apply sig figs in addition/subtraction and multiplication/division?

Please and thank you.

Addition or Subtraction:
The last digit retained is set by the first doubtful digit. (e.x.: 2.042 + 3.2 - 0.123 = 5.365-> 5.4 since the 3.2 is the most doubtful because it only has one digit after the decimal so you round to that decimal point)
Multiplication or Division:
The answer contains no more significant figures than the least
accurately known number. (e.x.: 2.711 * 6.3 = 17.0793 -> 17 since 6.3 has two sig figs so the answer can only have two sig figs)

On another note, make sure to wait until you get your final answer to round sig figs. In other words, do not round your sig figs in the middle of your problem.