Number of Significant Figures in Result of Addition or Subtraction/Examples/83.42 - 72

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

$83 \cdotp 42 - 72 = 11$

Proof

We have that:

the least significant digit $d_m$ of $83 \cdotp 42$ is the $10^{-2}$ position

the least significant digit $d_n$ of $72$ is the $10^0$ position.

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

the least significant digit of $83 \cdotp 42 - 72$ is the greater significant digit of $10^{-2}$ and $10^0$, that is $10^0$.

\(\ds 83 \cdotp 42 - 72\)

\(=\)

\(\ds 11 \cdotp 42\)

by calculation

\(\ds \)

\(=\)

\(\ds 11\)

to the nearest $10^0$

$\blacksquare$

Sources

• 1972: Murray R. Spiegel and R.W. Boxer: Theory and Problems of Statistics (SI ed.) ... (previous) ... (next): Chapter $1$: Computations: Example 2.