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Stage: 1 and 2 Challenge Level:
Christopher from Seoul Foreign School (SFS)  in South Korea (Korea Republic)  wrote:

The fastest way put the numbers from $1-100$ in one grid is by putting every number that has a zero at the end of the number in the tenth column. One in the first column. Two in the second column. The grid has to start with a 1 or else if there was a zero you would have to skip out the hundred.  The zero placed numbers go in the tenth place column because of this:
$1-2-3-4-5-6-7-8-9-10$
The ten is in the tenth column or the tenth place.
This gets control of the pattern.
$10$
$20$
$30$
$40$
$50$
$60$
$70$
$80$
$90$
$100$
I hope you understand my solution. Rei was sick today so I'll just put on my name. Thank you.

Felicity  from St. Anselm's in England wrote:

To put the numbers back on, I would start with the smallest number and go along until I get to the next gap and carry on until they're all in place.

Thank you, it was just these two that wrote in for this problem.