What's Possible?

Many numbers can be expressed as the difference of two perfect squares. What do you notice about the numbers you CANNOT make?

What's it Worth?

There are lots of different methods to find out what the shapes are worth - how many can you find?

Magic Squares for Special Occasions

This article explains how to make your own magic square to mark a special occasion with the special date of your choice on the top line.

Simultaneous Multiplying

Stage: 4 Short Challenge Level:

$10\frac{1}{2}$

From the three equations we see that $(abc)^2=2\times 24\times 3=144$ and so, since $abc$ is positive, $abc=12$. Then the third equation tells us that $a=1/2$, the second that $b=4$ and the first that $c=6$. Therefore $a+b+c=10\frac{1}{2}$.

This problem is taken from the UKMT Mathematical Challenges.