Dividing a fraction by a fraction might seem confusing at first, but it is really very simple. All you need to do is flip the second fractions, multiply, and reduce! This article will guide you through the process , give you sample problems to solve, and show you that dividing fractions by fractions is really a breeze. We’ve also spoken to academic tutor David Jia and math teacher Grace Imson for their expert advice on dividing fractions by each other.
Solving for a Fraction Divided by a Fraction
Flip the numerator and denominator on the second fraction to get the reciprocal, says math teacher Grace Imson. Then, multiply the two numerators together to get the numerator of your final answer. Then, multiply the denominators together to get the denominator of your final answer. Simplify the fractions, if needed.
Steps
How to Divide a Fraction by a Fraction
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Identify your dividend fraction and your divisor fraction. You should have two fractions. The first fraction is the fraction that’s being divided—this is called your dividend fraction . The second fraction is the one that’s being divided by —this is called your divisor fraction . [1] X Research source
- Example:
- For our example problem, we’ll use 2/3 ÷ 3/7 .
- 2/3 is our dividend fraction, while 3/7 is our divisor fraction.
- Example:
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Flip the numerator and denominator on the divisor fraction. Your divisor fraction (or the second fraction) has a numerator at the top and a denominator at the bottom. Flip the fraction so your denominator is now at the top and the numerator at the bottom. This is called finding the reciprocal of your fraction . [2] X Research source
- Example:
- 3/7 is our divisor fraction. If we flip the fraction, the reciprocal is 7/3.
Advertisement - Example:
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Multiply each fraction’s numerator and denominator by the other one. In order to divide fractions, we actually want to multiply them ! First, multiply the numerators of your two fractions together—the result of this calculation will become the numerator of your final answer. Then, multiply the denominators of your two fractions together—the result of this calculation will become the denominator of your final answer. [3] X Research source
- Example:
- 2 x 7 = 14 , so our numerator is 14.
- 3 x 3 = 9 , so our denominator is 9.
- This means that our final result is 14/9.
- Example:
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Simplify the fraction (if needed) to its simplest form. If your fraction is already in its simplest form (e.g., 1/2, 2/3, 3/4, 5/7, etc.), then you’re done! If your fraction can still be simplified, however, then you must reduce it to its simplest form. To simplify a fraction , find the greatest common factor between the numerator and denominator (i.e., the largest number that both of them can be divided by), instructs Jia. Then, divide both the numerator and denominator by the greatest common factor. The resulting numbers are your new numerator and denominator in the simplest form of your fraction. [4] X Expert Source David Jia
Academic Tutor Expert Interview. 7 January 2021.- In common terms, clarifies Jia, you just have to ask yourself “what is the biggest number that both the top and bottom can be divided by? What’s the biggest number that both numbers can be divided by?” [5]
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Expert Source
David Jia
Academic Tutor Expert Interview. 7 January 2021. - Example:
- In our example, the final result has a numerator (14) that’s larger than the denominator (9), meaning that we have to convert the fraction to a mixed number (a whole number and fraction combined, like 1⅔) before simplifying it.
- We’ll first divide the numerator (14) by the denominator (9). 9 goes into 14 one time, with a remainder of 5, giving us this fraction → 1 5/9 (“one and five-ninths”).
- That’s our answer! The fraction can’t be reduced further because the denominator is not evenly divisible by the numerator (i.e., 9 can’t be evenly divided by 5) and the numerator is a prime number (an integer that can only be divided by one and itself).
- In common terms, clarifies Jia, you just have to ask yourself “what is the biggest number that both the top and bottom can be divided by? What’s the biggest number that both numbers can be divided by?” [5]
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Expert Source
David Jia
Community Q&A
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QuestionWhat is 2 1/2 divided by 1/2?DonaganTop AnswererChange the mixed number to an improper fraction: 2½ becomes 5/2. Then invert ½ to become 2/1. Multiply 5/2 by 2/1, and reduce or simplify if possible. (5/2)(2/1) = 10/2 = 5.
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QuestionHow do I divide 3/4 by 3/5?DonaganTop AnswererInvert 3/5 to 5/3, and multiply by ¾: (3/4) x (5/3) = 15/12 = 5/4 or 1¼.
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QuestionHow do I find the reciprocal of a whole number?DonaganTop AnswererThe reciprocal is a fraction whose numerator is 1 and whose denominator is the whole number. For example, if the whole number is 5, think of it as 5/1, then invert that fraction to 1/5.
Video
Tips
References
- ↑ http://www.amathsdictionaryforkids.com/qr/d/division.html
- ↑ https://opentextbc.ca/mathfortrades1/chapter/dividing-fractions/
- ↑ https://resourcecenter.byupathway.edu/math/fractions/dividing-fractions
- ↑ David Jia. Academic Tutor. Expert Interview. 7 January 2021.
- ↑ David Jia. Academic Tutor. Expert Interview. 7 January 2021.
- ↑ https://thirdspacelearning.com/blog/how-to-divide-fractions/
- ↑ Grace Imson, MA. Math Instructor, City College of San Francisco. Expert Interview. 1 November 2019.
- ↑ https://opentextbc.ca/mathfortrades1/chapter/dividing-fractions/
About This Article
To divide fractions by fractions, start by replacing the division sign with a multiplication sign. Then, flip the second fraction over so the bottom number of the second fraction is now on the top. Multiply the top numbers of both fractions together to get the numerator (top number) of your new fraction. To get the denominator (bottom number) of your new fraction, multiply the bottom numbers of both fractions together. Simplify your fraction and you're finished! For actual examples of fractions being divided, read the article!
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