problem
Favourite
How old am I?
In 15 years' time my age will be the square of my age 15 years ago. Can you work out my age, and when I had other special birthdays?
problem
Favourite
Beelines
Is there a relationship between the coordinates of the endpoints of a line and the number of grid squares it crosses?
problem
Favourite
Multiplication arithmagons
Can you find the values at the vertices when you know the values on the edges of these multiplication arithmagons?
problem
Favourite
Difference of Two Squares
What is special about the difference between squares of numbers adjacent to multiples of three?
problem
Favourite
Square Number Surprises
There are unexpected discoveries to be made about square numbers...
problem
Favourite
Which is bigger?
Which is bigger, n+10 or 2n+3? Can you find a good method of answering similar questions?