Parents Guide to Parents Guide to Long MultiplicationLong Multiplication

This Power Point Presentation will This Power Point Presentation will Show Parents the Language We Show Parents the Language We Use When Teaching Children Long Use When Teaching Children Long MultiplicationMultiplication

Introducing Long Introducing Long MultiplicationMultiplication

We introduce long We introduce long multiplication first of all by multiplication first of all by

looking at multiplying by looking at multiplying by 20, 30, 40 etc.20, 30, 40 etc.

ExampleExample

54 6254 62

X20X20 x30x30

Always multiply by the Always multiply by the units first:units first:

5454

X 20X 20

We say, “54 multiplied by zero.”We say, “54 multiplied by zero.”

Then we say, “54 multiplied by 2.”Then we say, “54 multiplied by 2.”

Multiplying by 20Multiplying by 20

5 4

x 20

We introduce this calculation by saying:

54 multiplied by zero is zero.

When we multiply by zero the answer is always zero!

Put your zero in the answer.

Now we multiply 54 by 2.

We say 2 fours are 8. Put down your 8.

Now we say 2 fives are 10.

This is the end of the sum so put down the 10 in the answer.

8

010

Example 2Example 2

4 6

x 20

We introduce this calculation by saying:

46 multiplied by zero is zero.

When we multiply by zero the answer is always zero!

Put your zero in the answer.

Now we multiply 46 by 2.

We say 2 sixes are 12. Put down your 2 and carry your 1.

Now we say 2 fours are 8 add 1 is 9.

This is the end of the sum so put down the 9 in the answer.

2

09 1

Try These:Try These:

Remember: when we multiply by zero, the answer is always zero!

5252

X 20X 204848

X 40X 402929

X 30X 30

9595

X 40X 403434

X 20X 208383

X 30X 30

9494

X 40X 402828

X 50X 503434

X60X60

Long MultiplicationLong Multiplication

Long multiplication is really 3 sums in one!Step 1: multiply the top number by the units digit in the bottom number.

Step 2: Multiply the top number by the tens digit in the bottom number.

Step 3: add your two answers.

Step 1Step 1 Step 2Step 2 Step 3Step 3

3232

X X 2323

3232

X 3X 3

9696

3232

X 20X 20

640640

9696

+640+640

Be careful with your place value!Be careful with your place value!

To remind us to keep the figures in the correct place, we talk about the magic 0!

46

X23

138 Multiply 46 by 3

920 Put in your magic nought! Now do 46 multiplied by 2

1058 Finally add your two answers together!

Notice that without your magic nought the digits 9 and 2 would not be in the correct place & your answer would be incorrect.

Now try these:Now try these:

Remember: Long multiplication is really 3 sums in one!

Step 1: multiply the top number by the units digit in the bottom number.

Step 2: Multiply the top number by the tens digit in the bottom number.

Step 3: add your two answers.

7676

X23X238282

X46X469393

X54X54

3232

X 41X 414646

X 54X 546464

X 32X 32

We hope this powerpoint will help We hope this powerpoint will help you to work with your child at you to work with your child at home.home.

Please ask in school if you have any Please ask in school if you have any questions regarding our approach questions regarding our approach to teaching maths.to teaching maths.

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