# Sig figs

1. Sep 2, 2014

### Teachme

I was reading a problem my brother was assigned in his introductory physics course. The problem specifically asks to give the velocity from viewing a graph. The velocity is 2/3 m/s and it asked to give it in two significant figures. So I thought it would be .66, however the online site he was doing it on said this was incorrect and said the answer was 0.6. I do not agree with this since I was always led to believe the 0 is not a significant figure. Am I incorrect to say that the answer is .66 for two sig figs? I think they just made a mistake. Or am I missing something?

2. Sep 2, 2014

### Teachme

I meant to say 0 is not significant figure when to the left of other numbers.

3. Sep 2, 2014

### ehild

You are right, the zeros "to the left " indicate the magnitude. Writing the number in normal form, 2/3 = 0.66= 6.6 x 10-1 with two significant figures.
Imagine you have to give 2/30 with two significant figures. It is not 0.0!

ehild

4. Sep 2, 2014

### billy_joule

I would call it 0.67.

5. Sep 2, 2014

### ehild

Well, of course!

ehild