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# Double Digit

##### Age 11 to 14Challenge Level

Choose two digits and arrange them to make two double-digit numbers, for example:

If you choose $1$ and $2$,
you can make $12$ and $21$

Try lots of examples. What happens? Can you explain it?

What happens if you choose zero as one of the digits?

Try to explain why.

How does it work if you choose the same digits, for example $3$ and $3$?

What happens if you use negative numbers?

Now choose three digits and arrange them to make six different triple-digit numbers.