Significant figures combination calculations?

Question

How do I calculate sig figs when in the problem there is addition/subtraction AND multiplication/division?

Answer 1

Do it step by step. Take significant figures after each step you do and move on. If multp/div is first, do sig figs first for that then move on.  

Answer 2

The amount of sig figs will be determined by the number with the lowest amount. So for example, 3.45 + 12.60 would be 16.05. However, because 3.45 has only 3 sig figs, the answer is actually 16.1. Then say you have to multiply it by 2.0. So you get an answer of 32.2, but 2.0 has only 2 sig figs, so your answer is 32.

Basically, you will keep adjusting your sig figs throughout the equation if the significant figures aren't the same.