Chapter SR9, Problem 18P

Solution

To perform the calculation $10.0\text{}\text{liters of water}-\text{4}\text{.5 liters of water}$ and write the answer with appropriate number of significant digits.

  $5.5\text{ liters of water}$

Given:

The expression, $10.0\text{}\text{liters of water}-\text{4}\text{.5 liters of water}$ .

Concept Used:

Significant digits

• All nonzero digits are significant.
• All zeros that appear between two nonzero digits are significant.
• For a decimal, all zeros that appear after the last nonzero digit are significant.
• The number of significant digits in the result of basic algebraic operations between two numbers is as many significant digits as the least number of significant digits in any of the numbers involved.

Calculation:

Note that there are 3 significant digits in 10.0 and 2 significant digits in 4.5, so the final answer should have 2 significant digits as shown below

  $\begin{array}{c}10.0-4.5=5.5\\ =5.5\text{ liters of water}\end{array}$

Thus, the simplified expression with appropriate significant digits is $5.5\text{ liters of water}$ .