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Have You Got It?

Can you explain the strategy for winning this game with any target?

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Counting Factors

Is there an efficient way to work out how many factors a large number has?

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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.

Adding All Nine

Age 11 to 14 Challenge Level:
Remember to check your adding.
See how many $2$-digit numbers you can find that are divisible by $9$.
What happens if you just use the numbers from $1$ to $8$?