Method in Multiplying Madness?
These printable resources may be useful: Methods in Multiplying Madness,
Methods in Multiplying Madness Support.
If you had to work out $23 \times 21$ how would you do it?
What if you needed to work out $246 \times 34$?
Here are eight videos showing four different methods for working out the two multiplications. Can you make sense of them?
Grid Multiplication
$23 \times 21$
$246 \times 34$
Column Multiplication
$23 \times 21$
$246 \times 34$
Multiplying with Lines
$23 \times 21$
$246 \times 34$
Gelosia Multiplication
$23 \times 21$
$246 \times 34$
Once you have watched the videos, make up some multiplication calculations of your own and have a go at answering them using all four methods. Check that you get the same answer each time!
Here are some questions to consider:
Why does each method work?
What do the methods have in common?
What are the advantages and disadvantages to each method?
Extension challenge
Here is a video of another multiplication method, one where no writing down is needed along the way. Can you make sense of the video, and explain how this method works?
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