Learning Outcomes
- Use the order of operations to simplify expressions that contain decimals
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?
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]
Show Solution
try it
The following two videos contain more examples of how to use the order of operations to simplify expressions with decimals.
