How do you round 1721.344 to three significant figures?

May 11, 2017

Refer to this answer for more information on significant figures.

Significant figures are simply for telling you how much precision you have in your result. That is, how sure are you to what decimal place that your answer is exact?

To three significant figures, we retain only the nonzero digits and round down since the fourth digit is less than $5$...

$\implies \textcolor{b l u e}{1720}$

or if we wish to write it in scientific notation...

$\implies \textcolor{b l u e}{1.72 \times {10}^{3}}$

How many significant figures does $1721.344$ have to begin with?