Counting with zeros
You learn to work with numbers that end in zeros: leave the zeros off for a moment, then put them back.
How to work it out
- Count the zeros on the end of the numbers.
- Take them off and work with the small numbers.
- Put the same number of zeros back on the end.
- When you divide, take the same zeros off both numbers.
5600 + 800
- Look at the zeros: both numbers end in two zeros.
- Take them off: 56 + 8.
- Work it out: 56 + 8 = 64.
- Put the 2 zeros back: 6400.
More examples
40 × 30
- Take off the 2 zeros: 4 × 3.
- Multiply: 4 × 3 = 12.
- Put the 2 zeros back: 1200.
2800 ÷ 4
- Take off the 2 zeros: 28 ÷ 4.
- Use the times table: 28 ÷ 4 = 7.
- Put the 2 zeros back: 700.
34 × 100
- 100 has 2 zeros.
- Put 2 zeros on the end of 34: 34 × 100 = 3400.