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problem
Favourite
The Tall Tower
5 to 7
As you come down the ladders of the Tall Tower you collect useful spells. Which way should you go to collect the most spells?
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A Complex Mistake?
Discover how Heron of Alexandria missed his chance to explore the unknown mathematical land of complex numbers.
problem
Slippy Numbers
11 to 14
The number 10112359550561797752808988764044943820224719 is called a
'slippy number' because, when the last digit 9 is moved to the
front, the new number produced is the slippy number multiplied by
9.
problem
In Particular
14 to 16
Can you find formulas giving all the solutions to 7x + 11y = 100 where x and y are integers?
problem
Basically
11 to 14
The number 3723 (in base 10) is written as 123 in another base. What is that base?
problem
Power Crazy
11 to 14
What can you say about the values of n that make $7^n + 3^n$ a multiple of 10? Are there other pairs of integers between 1 and 10 which have similar properties?
problem
Arrange the Digits
11 to 14
Can you arrange the digits 1,2,3,4,5,6,7,8,9 into three 3-digit
numbers such that their total is close to 1500?
problem
Totality for Two
5 to 11
Totality game for an adult and child. Be the first to reach your agreed total.