Algorithms

problem
Method in multiplying madness?

Age

7 to 14

Challenge level

Watch our videos of multiplication methods that you may not have met before. Can you make sense of them?
problem
Medal muddle

Age

11 to 14

Challenge level

Countries from across the world competed in a sports tournament. Can you devise an efficient strategy to work out the order in which they finished?
problem
Skeleton

Age

11 to 14

Challenge level

Can you reconstruct the long division calculation from the 'skeleton'?
problem
Zeller's birthday

Age

14 to 16

Challenge level

What day of the week were you born on? Do you know? Here's a way to find out.
problem
Peaches in general

Age

14 to 16

Challenge level

It's like 'Peaches Today, Peaches Tomorrow' but interestingly generalized.
problem
Triangle incircle iteration

Age

14 to 16

Challenge level

Keep constructing triangles in the incircle of the previous triangle. What happens?
problem
Vedic sutra - all from 9 and last from 10

Age

14 to 16

Challenge level

Vedic Sutra is one of many ancient Indian sutras which involves a cross subtraction method. Can you give a good explanation of WHY it works?
problem
Unusual long division - square roots before calculators

Age

14 to 16

Challenge level

However did we manage before calculators? Is there an efficient way to do a square root if you have to do the work yourself?
problem
Sorted

Age

14 to 18

Challenge level

How can you quickly sort a suit of cards in order from Ace to King?
article
Divided differences

When in 1821 Charles Babbage invented the `Difference Engine' it was intended to take over the work of making mathematical tables by the techniques described in this article.