Take any 4 digit number. Create a second 4 digit number from the first one by reordering the
digits. Then subtract the smaller number from the larger one.
Pick a digit from the second number, but do not choose a zero.
Tell me the other three numbers and I will tell you what number you choose.
How do I do this?
Try it out at http://digicc.com/fido/
digits. Then subtract the smaller number from the larger one.
Pick a digit from the second number, but do not choose a zero.
Tell me the other three numbers and I will tell you what number you choose.
How do I do this?
Try it out at http://digicc.com/fido/
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