12-05-2007
Sorry if this is really late, I see that this topic is a week old, but maybe I can still be of service.
It's over 3.0 so the way to get 4 sig-figs is by making 400 into 4.0X10^2
400 is only 1 sig-fig, but 400.0 is effectively 4 sig-figs, so the only way to appropriately make it exactly 2 is the way I mentioned above.
PS, yzfrydn is also correct, but in my opinion, this is the easiest way to never fail at getting correct sig-figs. |