Learning Long Division

Teachers-if you are doing this live, consider making a copy and deleting slides that have examples/answers as you will be doing that with students.

The whole version could be made available at a later time to students for review or to for students who are remote.

DMSB

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What is DMSB? You wonder?

This stands for the order of long division

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Divide

Multiply

Subtract

Bring Down

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2

Using Models for division

Division

Area Model

Watch the video to review

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Let’s Explain

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Take a look at this division problem:

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3 )74

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The answer to this problem will be the quotient.

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5

This is the divisor.

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The divisor is the number of groups we are dividing into or the number we are dividing by.

This is the dividend.

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The dividend is the number we break into groups.

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Let’s start with our equation and figure out how many groups of 2 will go into 468.

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Think of larger multiplication numbers to save time. Use numbers that are easy to work with. For example,

2 x 200 = 400

2 x 300 =600

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Since 2 x 200 = 400. Let’s put the 200 on the side.

Multiply 2 x 200 and then subtract from 468.

6

468

2

200

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400

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68

Now we need to figure out how many groups of 2 will go into 68.

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Think of multiplication numbers. Use numbers that are easy to work with. For example,

2 x 10 = 20

2 x 20 = 40

2 x 30 =60

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Since 2 x 30 = 60. Let’s put the 30 on the side.

Multiply 2 x 30 and then subtract from 68.

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468

2

200

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400

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68

30

60

8

Now we need to figure out how many groups of 2 will go into 8.

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I know that 2 x 4 = 8. Let’s put the 4 on the side.

Multiply 2 x 4 and then subtract from 8.

8

468

2

200

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400

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68

30

60

8

8

4

0

We are left with 0, this means we have no remainder.

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We need to add up all of the partial quotients to get our answer.

200 + 30 + 4 =234.

2 will go into 468

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Let’s check:; 234 x 2 =468!!

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9

468

2

200

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400

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68

30

60

8

8

4

0

234 times.

Watch the video for more review.

DIVIDE

You want to find the closest number to 70 without going over!

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In this case it’s

23 times because

3 x 23 is 69

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24 times is too high since 3 x 24 = 72

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Let’s put our number in the tens spot and multiply

3 x 23=69. Let’s put that number under 70 and subtract.

Move what is left over to the next column.

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3

Multiply and Subtract

Now how many times will 3 go into 5 without going over?

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x

23

DIVIDE

You want to find the closest number to 5 without going over!

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In this case it’s

1 times because

3 x 1 is 3

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2 times is too high since 3 x 2 = 6

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13

Let’s put our number in the ones spot and multiply

3 x 1. When we multiply, we get 3. Let’s put that number under 5 and subtract.

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3

1

23

x

Multiply and Subtract

We have no more numbers to bring down! Let’s add up the numbers on the top of our model to get our answer.

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3

What’s Left?

1

23

x

The remainder is what you have left over (or what is remaining) after you have nothing to bring down:

Let’s add up the numbers on top of our table. 23 + 1 =24.

This means that 3 divides into 74, 24 times with a remainder of 2

So the answer is 24 R.2

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3

Final Steps

1

23

x

The remainder is what you have left over (or what is remaining) after you have nothing to bring down:

Practice Kahoot

Click on the Kahoot and complete it!

Use either scratch paper to help you show your work.

Be prepared to hold your scratch paper up to the camera.

Your Turn

Extra Help?

If you still need help, check out this video. It is another way to use your area model to solve division problems.

Solve the Problems Using Area Model

438 ➗6

Solve the Problems Using Area Model

261 ➗9

Solve the Problems Using Area Model

792 ➗4

Solve the Problems Using Area Model

530 ➗2

Works Cited

http://duplinschools.net/cms/lib01/NC01001360/Centricity/Domain/2229/LongDivision.ppt

Division using Models. (n.d.). Retrieved January 11, 2021, from https://www.mathworksheets4kids.com/division-models.php

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