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I'm Eight

Find a great variety of ways of asking questions which make 8.

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More Mods

What is the units digit for the number 123^(456) ?

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Repeaters

Choose any 3 digits and make a 6 digit number by repeating the 3 digits in the same order (e.g. 594594). Explain why whatever digits you choose the number will always be divisible by 7, 11 and 13.

What Is the Question?

Stage: 3 and 4 Challenge Level: Challenge Level:1

Image 1 hint
The answer is 49.
What is the question?
Why does it work?
Image 2 hint
The answer is 42.
What is the question?
Why does it work?
Image 3 hint
The answer is 63.
What is the question?
Why does it work?
Image 4 Hint
The answer is 56.
What is the question?
Why does it work?
See also this problem .