### There are 24 results

Broad Topics >

Decision Mathematics and Combinatorics > Algorithms

##### Age 16 to 18 Challenge Level:

Can you crack these very difficult challenge ciphers? How might you systematise the cracking of unknown ciphers?

##### Age 16 to 18 Challenge Level:

Fourth challenge cipher

##### Age 16 to 18 Challenge Level:

Is the regularity shown in this encoded message noise or structure?

##### Age 16 to 18 Challenge Level:

Second challenge cipher

##### Age 16 to 18 Challenge Level:

Third challenge cipher

##### Age 16 to 18 Challenge Level:

Fifth challenge cipher

##### Age 16 to 18 Challenge Level:

Seventh challenge cipher

##### Age 16 to 18 Challenge Level:

Sixth challenge cipher

##### Age 11 to 16

Scheduling games is a little more challenging than one might desire. Here are some tournament formats that sport schedulers use.

##### 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?

##### Age 14 to 16 Challenge Level:

It's like 'Peaches Today, Peaches Tomorrow' but interestingly
generalized.

##### Age 16 to 18 Challenge Level:

Can you interpret this algorithm to determine the day on which you were born?

##### Age 16 to 18 Challenge Level:

A sequence of numbers x1, x2, x3, ... starts with x1 = 2, and, if
you know any term xn, you can find the next term xn+1 using the
formula: xn+1 = (xn + 3/xn)/2 . Calculate the first six terms of
this. . . .

##### Age 14 to 18 Challenge Level:

How would you judge a competition to draw a freehand square?

##### Age 16 to 18

This article explains the concepts involved in scientific
mathematical computing. It will be very useful and interesting to
anyone interested in computer programming or mathematics.

##### Age 16 to 18 Challenge Level:

Can you think like a computer and work out what this flow diagram
does?

##### Age 14 to 16 Challenge Level:

Imagine a strip with a mark somewhere along it. Fold it in the middle so that the bottom reaches back to the top. Stetch it out to match the original length. Now where's the mark?

##### 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?

##### 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.

##### Age 16 to 18 Short Challenge Level:

In this short problem, can you deduce the likely location of the odd ones out in six sets of random numbers?

##### Age 16 to 18

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.

##### Age 11 to 18 Challenge Level:

A geometry lab crafted in a functional programming language. Ported
to Flash from the original java at web.comlab.ox.ac.uk/geomlab

##### Age 14 to 18 Challenge Level:

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

##### Age 14 to 16 Challenge Level:

Keep constructing triangles in the incircle of the previous triangle. What happens?