Image
The problems in this feature will give you the chance to investigate the properties of numbers in a variety of contexts. We hope that this will give you the opportunity to explore, conjecture and develop convincing arguments for any general results that you discover.
article
Divisibility tests
This article explains various divisibility rules and why they work. An article to read with pencil and paper handy.
problem
Favourite
Dozens
Age
7 to 14
Challenge level
Can you select the missing digit(s) to find the largest multiple?
problem
Clock arithmetic
Age
11 to 18
Challenge level
What happens if we change the rules and make the usual straight number line into a circle?
problem
Favourite
Stars
Age
11 to 14
Challenge level
Can you work out what step size to take to ensure you visit all the dots on the circle?
problem
Clock squares
Age
14 to 18
Challenge level
Can you find a way of predicting the value of large square numbers with the help of our power modulo calculator?
problem
More adventures with modular arithmetic
Age
14 to 18
Challenge level
Investigate what happens when we add or multiply numbers using modular arithmetic.
We are very grateful to the Heilbronn Institute for Mathematical Research for their generous support for the development of these resources.