Algorithms

There are 32 NRICH Mathematical resources connected to Algorithms
Tis Unique
problem

Tis unique

Age
11 to 14
Challenge level
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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.
X marks the spot
problem

X marks the spot

Age
11 to 14
Challenge level
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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" .
Archimedes and numerical roots
problem

Archimedes and numerical roots

Age
14 to 16
Challenge level
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The problem is how did Archimedes calculate the lengths of the sides of the polygons which needed him to be able to calculate square roots?
Stretching Fractions
problem

Stretching fractions

Age
14 to 16
Challenge level
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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?
Procedure solver
problem

Procedure solver

Age
16 to 18
Challenge level
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Can you think like a computer and work out what this flow diagram does?
Zeller's Birthday
problem

Zeller's birthday

Age
14 to 16
Challenge level
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What day of the week were you born on? Do you know? Here's a way to find out.
Peaches in General
problem

Peaches in general

Age
14 to 16
Challenge level
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It's like 'Peaches Today, Peaches Tomorrow' but interestingly generalized.
Divided Differences
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.