In this lesson, we will use some examples to explain the basics behind dividing fractions.
About This Lesson
It is quite easy to divide fractions after we learned how to multiply fractions. This is because dividing fractions is closely related to multiplying fractions.
This relation lies in the step needed to convert the division to multiplication. The picture on the right will give you a rough idea on this.
below will explain more.
Tip #1 - Reciprocal of a fraction
We need to know how to find the reciprocal of a fraction before we can proceed. The example below shows how:
Find the reciprocal of the following fraction:
To do so, we simply swap the numerator and denominator:
Hence, the reciprocal of
Tip #2 - Dividing Fractions
The following example shows the steps required to divide fractions:
First, we change the division to multiplication. Then, we change the divisor
, to its reciprocal,
After doing so, we can continue by multiplying these fractions:
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Math Video Transcript
00:00:02.220 In this lesson, we will learn the basics behind dividing fractions. 00:00:08.090 Let's divide, 1/5 with 3/4. 00:00:13.100 We can do so, by changing this division sign to multiplication sign, provided that we swap the numerator and denominator of the divisor, 3/4, to get its reciprocal, 4/3. 00:00:27.020 To explain this, let's take a look at the division again. Note that, 1/5 divides by 3/4, can be written in the form of fraction, 1/5, over, 3/4. 00:00:42.160 Now, 1/5 is the numerator, and 3/4 is the denominator. 00:00:49.070 Next, let's multiply the denominator with 4/3. 00:00:54.130 To keep this fraction equivalent, we must multiply the numerator with 4/3 as well. 00:01:01.010 Next, notice that these terms cancel off. This is because, 4 divides by 4, and 3 divides by 3 gives 1. 00:01:11.150 Now, we are left with the numerator. Dividing this numerator with 1, gives back itself, 1/5 multiply by 4/3. 00:01:23.060 Here, notice something interesting. By comparing these 2 terms, we observe that this fraction division is the same as fractions multiplication, provided that we change the divisor, 3/4 to its reciprocal, 4/3. 00:01:41.050 Knowing this, let's continue the division by multiplying these fractions. 00:01:47.200 First, multiply the numerators. 1 multiply by 4, gives 4. 00:01:56.050 Next, multiply the denominators. 5 multiply by 3, gives 15. 00:02:05.050 Finally, we have the fraction, 4/15. 00:02:12.220 Next example, let's divide 2/3, with 5/7. 00:02:18.210 We can do so, by changing this division sign to multiplication sign, provided that we swap the numerator and denominator of the divisor, 5/7, to get its reciprocal, 7/5. 00:02:33.080 Now, we can proceed by multiplying these fractions. 00:02:38.120 First, multiply the numerators. 2 multiply by 7, gives 14. 00:02:46.020 Next, multiply the denominators. 3 multiply by 5, gives 15. 00:02:54.060 Finally, we have the fraction, 14/15. 00:03:00.160 This is all for this lesson, try out the practice questions to further your understanding. --End of Dividing Fractions Transcript--
Practice Questions & More
Multiple Choice Questions (MCQ)
Now, let's try some MCQ questions to understand this lesson better.
You can start by going through the series of
questions on Dividing Fractions
or pick your choice of question below.
on the basics
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