Multiplying and Dividing Numbers in Scientific Notation
Learning Outcomes
Multiply numbers expressed in scientific notation
Divide numbers expressed in scientific notation
Multiplying Numbers Expressed in Scientific Notation
Numbers that are written in scientific notation can be multiplied and divided rather simply by taking advantage of the properties of numbers and the rules of exponents that you may recall. To multiply numbers in scientific notation, first multiply the numbers that aren’t powers of 10 (the a in [latex]a\times10^{n}[/latex]). Then multiply the powers of ten by adding the exponents.
This will produce a new number times a different power of [latex]10[/latex]. All you have to do is check to make sure this new value is in scientific notation. If it isn’t, you convert it.
Multiply [latex]4[/latex] by [latex]2[/latex] and use the Product Property to multiply [latex]{10}^{5}[/latex] by [latex]{10}^{-7}[/latex].
[latex]8\times {10}^{-2}[/latex]
Change to decimal form by moving the decimal two places left.
[latex]{\Large\frac{8}{100}} = 0.08[/latex]
try it
In the following video you will see an example of how to multiply tow numbers that are written in scientific notation.
Dividing Numbers Expressed in Scientific Notation
In order to divide numbers in scientific notation, you once again apply the properties of numbers and the rules of exponents. You begin by dividing the numbers that aren’t powers of [latex]10[/latex] (the a in [latex]a\times10^{n}[/latex]. Then you divide the powers of ten by subtracting the exponents.
This will produce a new number times a different power of 10. If it isn’t already in scientific notation, you convert it, and then you’re done.
Divide [latex]9[/latex] by [latex]3[/latex] and use the Quotient Property to divide [latex]{10}^{3}[/latex] by [latex]{10}^{-2}[/latex] .
[latex]3\times {10}^{5}[/latex]
Change to decimal form by moving the decimal five places right.
[latex]300,000[/latex]
try it
Notice that when you divide exponential terms, you subtract the exponent in the denominator from the exponent in the numerator. You will see another example of dividing numbers written in scientific notation in the following video.
The following video is a mini-lesson on how to convert decimals to scientific notation, and back to a decimal. Additionally, you will see more examples of how to multiply and divide numbers given in scientific notation.
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Examples: Dividing Numbers Written in Scientific Notation. Authored by: James Sousa (Mathispower4u.com) for Lumen Learning. Located at: https://youtu.be/RlZck2W5pO4. License: CC BY: Attribution
Examples: Multiplying Numbers Written in Scientific Notation. Authored by: James Sousa (Mathispower4u.com) for Lumen Learning. Located at: https://youtu.be/5ZAY4OCkp7U. License: CC BY: Attribution