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Days and Dates
Investigate how you can work out what day of the week your birthday will be on next year, and the year after...
Differences
Can you guarantee that, for any three numbers you choose, the product of their differences will always be an even number?
Where Can We Visit?
Charlie and Abi put a counter on 42. They wondered if they could visit all the other numbers on their 1-100 board, moving the counter using just these two operations: x2 and -5. What do you think?
Age 11 to 14 Challenge Level:
Explain why the arithmetic sequence
1, 14, 27, 40, ...
contains many terms of the form 222...2 where only the digit 2 appears. How many twos appear in these terms?
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NRICH is part of the family of activities in the Millennium Mathematics Project.
NRICH is part of the family of activities in the Millennium Mathematics Project.