Dividing Fractions has A monster Rule

Dividing fractions can be a little tricky. It’s the just operation that needs using the reciprocal. Making use of the mutual simply means you flip the portion over, or invert it.

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For example, the reciprocal of 2/3 is 3/2.

After we give you the department rule, we will show you WHY you need to use the mutual in the an initial place.

But for now…

Here’s the preeminence for Division

To divide, convert the fraction department process come a multiplication procedure by making use of the complying with steps.

Change the “÷” (division sign) come “x” (multiplication sign) and also invert the number to the right that the sign.Multiply the numerators.Multiply the denominators.Re-write your answer in its simplified or decreased form, if needed

Once you complete Step #1 for splitting fractions, the difficulty actually transforms from division to multiplication.

Example 1: separating Fractions by Fractions

1/2 ÷ 1/3 = 1/2 x 3/1

1/2 x 3/1 = 3/2

Simplified prize is 1 1/2

Example 2: dividing Fractions by whole Numbers

1/2 ÷ 5 = 1/2 ÷ 5/1

(Remember come convertwhole numbers to fractions, FIRST!)

1/2 ÷ 5/1 = 1/2 x 1/5

1/2 x 1/5 = 1/10

Example 3: dividing Whole number by Fractions

6 ÷ 1/3 = 6/1 ÷ 1/3

(Remember to convertwhole number to fractions, FIRST!)

6/1 ÷ 1/3 = 6/1 x 3/1

6/1 x 3/1 = 18/1 = 18

Now that’s every there is to it. The main things you need to remember as soon as you division is to transform whole number to fountain first, climate invert the fraction to the right the the department sign, and adjust the authorize to multiplication.

The “divisor” has actually some other considerationsyou should keep in mind…

Special Notes!Remember to only invert the divisor.The divisor’s numerator or denominator have the right to not it is in “zero”.Convert the operation to multiplication BEFORE performing any cancellations.

I promised to shot to explain why the preeminence requires inverting the divisor.

Here goes..

Why dividing Fractions requires Inverting The Divisor

Let’s use our an easy example to actually validate this strange dominion for division.

If you yes, really think about it, us are splitting a fraction through a fraction, which develops what is referred to as a “complex fraction”. It actually looks favor this…

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When working with complicated fractions, what we want to do very first is get rid of the denominator (1/3), therefore we have the right to work this difficulty easier.

You may recall that any number multiply by its mutual is same to 1. And also since, 1/3 x 3/1 = 1, we deserve to use the reciprocal home of 1/3, (3/1), to make the worth of the denominator same to 1.

You might likewise recall that every little thing we execute to the fraction’s denominator, we must likewise do come its numerator, for this reason as no to readjust the overall portion “value”.

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So let’s multiply both the numerator and denominator by 3/1…

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Which offers us…

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Here’s what happened…

By multiply the numerator and also denominator of our complicated fraction through 3/1, we were then able to usage the reciprocal property of a portion to remove the denominator. Actually, there is no our advantageous Rule, we would have to use every one of the procedures above.

So, the Rule for separating fractions really conserves us a lot of steps!

Now that’s the simplest explanation I could come up with for WHY and also HOW we end up with a Rule that says whenever we divide fractions, us must invert the divisor!