Learning Outcomes
- Simplify expressions containing decimals using the order of operations
The order of operations introduced in an earlier lesson also applies to decimals. Do you remember what the phrase “Please excuse my dear Aunt Sally” stands for? For a review on how to perform order of operations, you can go to this page.
example
Simplify the expressions:
1. [latex]7\left(18.3 - 21.7\right)[/latex]
2. [latex]{\Large\frac{2}{3}}\left(8.3 - 3.8\right)[/latex]
Solution
| 1. | |
| [latex]7\left(18.3 - 21.7\right)[/latex] | |
| Simplify inside parentheses. | [latex]7\left(-3.4\right)[/latex] |
| Multiply. | [latex]-23.8[/latex] |
| 2. | |
| [latex]{\Large\frac{2}{3}}\left(8.3 - 3.8\right)[/latex] | |
| Simplify inside parentheses. | [latex]{\Large\frac{2}{3}}\left(4.5\right)[/latex] |
| Write [latex]4.5[/latex] as a fraction. | [latex]{\Large\frac{2}{3}}\left({\Large\frac{4.5}{1}}\right)[/latex] |
| Multiply. | [latex]{\Large\frac{9}{3}}[/latex] |
| Simplify. | [latex]3[/latex] |
try it
For more examples similar to the ones above, watch the following video
example
Simplify each expression:
1. [latex]6\div 0.6+\left(0.2\right)4-{\left(0.1\right)}^{2}[/latex]
2. [latex]{\left({\Large\frac{1}{10}}\right)}^{2}+\left(3.5\right)\left(0.9\right)[/latex]
try it
The following two videos contain more examples of how to use the order of operations to simplify expressions with decimals.
