### Become an OU student

Numbers, units and arithmetic

Start this free course now. Just create an account and sign in. Enrol and complete the course for a free statement of participation or digital badge if available.

# 1.2 Using the place value

Writing numbers in place-value columns gives an easy way of multiplying by 10, 100, 1000 and so on. Have a look at the place value table again.

 Millions Hundred Thousands Ten Thousands Thousands Hundreds Tens Units

Notice that moving all the digits one column to the left in the table (and adding a zero to the units column) is the same as multiplying by ten; for instance, ten tens are a hundred, ten hundreds are a thousand. If you move two columns to the left, you multiply by a hundred; for instance, a hundred tens are a thousand. Moving three columns to the left is equivalent to multiplying by a thousand, and so on.

## Example 2

After local government re-organisation a new council expects to receive cash payments in ten instalments from about 26 000 households. In order to negotiate the cash collection at post offices it needs to know how many payments are made altogether in a year. How many are there likely to be?