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Surprising Split

Age 7 to 11 Challenge Level:
Take a look at this video, which has no sound:

If you can't access YouTube, here is a direct link to the video: SurprisingSplit.mp4 

Click below if you would like to read a description of what happens in the video.


54 x 11 is written.
Below that, the 5 and 4 are written again but separated so that there is a gap between them. A curved line is drawn linking the 5 and 4 and an addition sign is written below it. The number 9 is written between the 5 and 4.
Below that, 594 = 54 x 11 is written.


What do you notice?
What would you like to ask?


You might want to watch the video again.

Can you re-create this trick for yourself for 54 x 11?
Try the trick for a different multiple of 11.  What happens?

Does the trick always work, for any multiple of 11?


This isn't really a trick, it's maths!  Can you explain why it works?

Thank you to David Frankau and Mr Hadfield from the Pointer School in Greenwich who drew our attention to a trick for the 11 times table, which we have adapted for this task.