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This activity is about the number of letters in the words representing numbers.
Let’s begin with the number 62.
If 62 was written in words, how many letters would there be?
Sixty-two
There are 8 letters
62 -> 8 ->

If 8 was written in words, how many letters would there be?
Eight
There are five letters
62 -> 8  -> 5->

If 5 was written in words, how many letters would there be?
Five
There are four letters
62 -> 8 -> 5 -> 4 ->
If 4 was written in words, how many letters would there be?
Four
There are four letters
62 -> 8 -> 5 -> 4 ->…
This sequence will continue with the number 4 for ever.
Choose a different number to start a ‘Four Ever’ sequence.

Can you predict how the sequence will end? Can you predict how long the sequence will be?

Observe these sequences
62 -> 8 -> 5 -> 4 ->…
5 -> 4 ->…
56 -> 8 -> 5 -> 4 ->…
123 -> 24 -> 10 -> 3 ->
5 -> 4 ->…
Try choosing a different number again. Didn’t you get the same number at the end?