 # Parents Guide to Long Multiplication

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Parents Guide to Long Multiplication
This Power Point Presentation will Show Parents the Language We Use When Teaching Children Long Multiplication

Introducing Long Multiplication
We introduce long multiplication first of all by looking at multiplying by 20, 30, 40 etc. Example X x30

Always multiply by the units first:
54 X 20 We say, “54 multiplied by zero.” Then we say, “54 multiplied by 2.”

Multiplying 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. 10 8

Example 2 4 6 x 20 2 9 We introduce this calculation by saying:
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. 9 2 1

Remember: when we multiply by zero, the answer is always zero!
Try These: 52 X 20 48 X 40 29 X 30 95 34 83 94 28 X 50 X60

Long multiplication is really 3 sums in one!
Step 1 Step 2 Step 3 32 X 23 X 3 96 X 20 640 +640 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.

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 Multiply 46 by 3 Put in your magic nought! Now do 46 multiplied by 2 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.

Remember: Long multiplication is really 3 sums in one!
Now try these: 76 X23 82 X46 93 X54 32 X 41 46 X 54 64 X 32 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.