Number of Significant Figures in Result of Addition or Subtraction/Examples/3.16 + 2.7

Example of Use of Number of Significant Figures in Result of Addition or Subtraction

 * $3 \cdotp 16 + 2 \cdotp 7 = 5 \cdotp 9$

Proof
We have that:
 * the leftmost significant figure $d_m$ of $3 \cdotp 16$ is the $10^{-2}$ position
 * the leftmost significant figure $d_n$ of $2 \cdotp 7$ is the $10^{-1}$ position.

So from Number of Significant Figures in Result of Addition or Subtraction:


 * the leftmost significant figure of $3 \cdotp 16 + 2 \cdotp 7$ is the rightmost of $10^{-2}$ and $10^{-1}$, that is $10^{-1}$.