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Fibonacci's Three Wishes 1

First of two articles about Fibonacci, written for students.

Arrow Arithmetic 1

The first part of an investigation into how to represent numbers using geometric transformations that ultimately leads us to discover numbers not on the number line.

A Story about Absolutely Nothing

This article for the young and old talks about the origins of our number system and the important role zero has to play in it.

Balance Power

Age 11 to 18
Challenge Level

Try weights from 1 to 15 units. Can you spot a pattern? Can you explain it? Now continue the pattern.

You might find the following spreadsheet tool useful for the last part of the problem.

The NRICH Project aims to enrich the mathematical experiences of all learners. To support this aim, members of the NRICH team work in a wide range of capacities, including providing professional development for teachers wishing to embed rich mathematical tasks into everyday classroom practice.
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