# How do you round 0.013946 to three significant figures?

Mar 18, 2017

0.0139

#### Explanation:

Significant figures are the first number(s) reading left to right that is non-zero.

In this case the 1 is the first significant figure, then the 3 and the 9. The 0's after the decimal point are to be left as they keep the other figures in the correct places. Looking at the digit after the 9 which is a 4 meaning that we round down.

Our answer is 0.013900 which is just 0.0139

Mar 18, 2017

$\textcolor{red}{0.0}$$\textcolor{b l u e}{139}$

#### Explanation:

Rules of significant figures,

1) Zeros before any number (1-9) $\textcolor{red}{i s}$ $\textcolor{red}{n o t}$ considered a significant number.
2) Zeros after any number (1-9) $\textcolor{red}{i s}$ considered a significant number.

$\textcolor{red}{R e d}$ is not considered a significant number and $\textcolor{b l u e}{b l u e}$ is considered a significant number, hence,

$\textcolor{red}{0.0}$$\textcolor{b l u e}{13946}$

Then, round-off the third $\textcolor{b l u e}{b l u e}$ number and you will get,

$\textcolor{red}{0.0}$$\textcolor{b l u e}{139}$