Skip to content
Exit presentation

A Story of Numbers

Start here

A shopkeeper counts bangles by the dozen, not one by one. A dozen is 12. Numbers can be written in many ways.

One count, three ways to write it.

This is Part I, Chapter 3: A Story of Numbers.

What you will learn

  • One mark each — the plainest count, and why it reads slowly.
  • Bundles — a gap every few marks turns marks into bundles.
  • Symbols added — some systems total the symbols written.
  • Where it sits — each column gives a symbol its own worth.
  • A mark for nothing — without it, two numbers look the same.
  • Ten symbols — position and a zero write every number.
  • Two ways of adding — one sum, two different costs.
  • Writing it down today — one amount, several ways to write it.

Every lesson has a lab. Move the numbers and watch the count change.

Jump to lesson

This track

  1. 0 Start here
  2. 1 One mark for one thing
  3. 2 Marks in bundles can be read at a glance
  4. 3 A number as the total of its symbols
  5. 4 Where a digit sits decides what it is worth
  6. 5 A mark for an empty place
  7. 6 Ten symbols will write any whole number
  8. 7 The same sum, worked out two ways
  9. 8 One number, several ways of writing it
  10. 9 The big picture
  11. 10 Track quiz

Other tracks