## What do you think is place value's favourite number?

- Well, how many ones are in ten?
- How many tens are in one hundred?
- How many hundreds are in one thousand?
- How many thousands are in ten thousand?
- How many ten thousands are in one hundred thousand?
- How many hundred thousands in one million?

Have you guessed it yet?
10!

Why do you think our ancestors all those years ago chose the number 10?

## Numbers in the Thousands

Remember that sometimes people don't write numbers above the thousands with a comma, sometimes they might just have a space instead, e.g. 80 976. Sometimes they don't even have a space, e.g. 80976, so you might want to put the space or comma in first to help you read the number.

## Why do we use different places?

Why do we have 'places' for numbers? Why not just keep creating more and more symbols for each number? Here's why...

(You may need to watch this one a few times, don't get too confused, it's trying to make you think outside the box).

How place value make large numbers look easy: We only need one abacus!

P.S. The abacus (shown above) was an ancient tool used for counting in the markets as far back as 500 B.C. That's over 2,500 years ago! People didn't want to have to use more than one abacus, so they made the different rows of beads worth different values, like ones, tens, hundreds, thousands, ten thousands, hundred thousands, millions, tens millions and so on. Or one row could we worth one bag of sugar, the second row could be worth one box of sugar, the third could be worth one wagon of sugar and so on.

Without using the power of 10 (grouping numbers by 10s), we would have to have a million DIFFERENT names for numbers. Imagine needing to remember all that! No thanks, I'll take our place value system based on groups of 10 any day.

Here's a chart of all our place values: Do you notice a pattern that keeps repeating itself every three places?

Hundreds - Tens - Ones in each set!

Here's another version with decimals added in. Do you notice the decimals pattern? Does it follow the same pattern as the other places or is it reversed?