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Geometry and measure

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Probability and statistics

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Working mathematically

  • Thinking mathematically
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Advanced mathematics

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For younger learners

  • Early Years Foundation Stage

Choose Your Units

Age 14 to 16
Challenge Level Yellow star
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Phenomena to units

Volume of a bacterium - Cubic micrometres $\mathrm{\mu m}^3$
Mass of an oak tree - Tonnes $(10^3\textrm{ kg})$
Area of a leaf - Square centimetres $(\textrm{cm}^2)$
Half-life of Uranium-235 - Millions of years
Area of a football pitch - Hectares
Average life-span of a human -Years
Volume of a bath tub - Cubic metres $(\textrm{m}^3)$

Units to phenomena

Millimetre - size of an amoeba
Newton - weight of an apple
Angstrom - atomic diameter of a hydrogen atom
Joule - kinetic energy of a table tennis ball travelling at $100\textrm{ km h}^{-1}$
Volt - voltage across an AA cell
Microgram - mass of $1\textrm{ mm}^3$ of air
Micrometre - mitochondrion
Hertz - frequency of tick-tock on a clock
Parsec - distance to Proxima Centauri (closest star other than the Sun)

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Bigger or Smaller?

When you change the units, do the numbers get bigger or smaller?

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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.

NRICH is part of the family of activities in the Millennium Mathematics Project.

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