1.06 Multiplication and division by 10 and 100
Are you ready?
Can you break a number into its parts , using place value?
Examples
Example 1
Complete the number expander for 27\,692.
| 27\,692 | = | ⬚ | \text{ten thousands} | ⬚ | \text{thousands} | ⬚ | \text{hundreds} | 9 | \text{tens} | 2 | \text{units} |
|---|
Write 27\,692 as a number sentence.
⬚+⬚+⬚+90+2
We can break a number into its parts by putting it in a place value table.
Multiply or divide by 10 and 100
The digits in our number tell us how many units, tens, hundreds or thousands (or more) we have. Remembering that each place is ten times larger than the place to its right can help us when we need to multiply or divide by 10.
Examples
Example 2
Fill in the boxes with the missing numbers.
6600\div⬚=66
When we multiply by 10, the digits move to the left one place, and our number gets bigger. We need to put a zero placeholder in the units place when we multiply by 10. When we divide by 10, our digits move to the right one place, and our number gets smaller.
When we multiply by 100, the digits move to the left two places, and our number gets bigger. We need to put zeros as placeholders in the tens and units places when we multiply by 100. When we divide by 100, our digits move to the right two places, and our number gets smaller.