Resources tagged with: Algorithms
There are 31 NRICH Mathematical resources connected to Algorithms, you may find related items under Decision mathematics and combinatorics.
Broad Topics > Decision mathematics and combinatorics > Algorithms
Probably a Code?
Is the regularity shown in this encoded message noise or structure?
Method in Multiplying Madness?
Watch our videos of multiplication methods that you may not have met before. Can you make sense of them?
Sorted
How can you quickly sort a suit of cards in order from Ace to King?
Stage 5 Cipher Challenge
Can you crack these very difficult challenge ciphers? How might you systematise the cracking of unknown ciphers?
The Best Square
How would you judge a competition to draw a freehand square?
Happy birthDay
Can you interpret this algorithm to determine the day on which you were born?
An Introduction to Computer Programming and Mathematics
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.
Peaches in General
It's like 'Peaches Today, Peaches Tomorrow' but interestingly generalized.
Zeller's Birthday
What day of the week were you born on? Do you know? Here's a way to find out.
Unusual Long Division - Square Roots Before Calculators
However did we manage before calculators? Is there an efficient way to do a square root if you have to do the work yourself?
Procedure Solver
Can you think like a computer and work out what this flow diagram does?
Stretching Fractions
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?
On What Day Did it Happen?
Read this article to find out the mathematical method for working out what day of the week each particular date fell on back as far as 1700.
Tournament Scheduling
Scheduling games is a little more challenging than one might desire. Here are some tournament formats that sport schedulers use.
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.
X Marks the Spot
When the number x 1 x x x is multiplied by 417 this gives the answer 9 x x x 0 5 7. Find the missing digits, each of which is represented by an "x" .
Tis Unique
This addition sum uses all ten digits 0, 1, 2...9 exactly once. Find the sum and show that the one you give is the only possibility.
Slippy Numbers
The number 10112359550561797752808988764044943820224719 is called a 'slippy number' because, when the last digit 9 is moved to the front, the new number produced is the slippy number multiplied by 9.
Vedic Sutra - All from 9 and Last from 10
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?
Medal Muddle
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?
Alphabet Soup
This challenge is to make up YOUR OWN alphanumeric. Each letter represents a digit and where the same letter appears more than once it must represent the same digit each time.
Skeleton
Amazing as it may seem the three fives remaining in the following `skeleton' are sufficient to reconstruct the entire long division sum.
Triangle Incircle Iteration
Keep constructing triangles in the incircle of the previous triangle. What happens?
Route to Root
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 sequence. What do you notice? Calculate a few more terms and find the squares of the terms. Can you prove that the special property you notice about this sequence will apply to all the later terms of the sequence? Write down a formula to give an approximation to the cube root of a number and test it for the cube root of 3 and the cube root of 8. How many terms of the sequence do you have to take before you get the cube root of 8 correct to as many decimal places as your calculator will give? What happens when you try this method for fourth roots or fifth roots etc.?