Place value: ones, tens and hundreds
๐ In short
In the number 333 there are three identical digits, but they have different values: the first is three hundreds, the second three tens and the third three ones. This is โplace valueโ: a digit's value changes with its place in the number.
๐คฉ Did you know?
- A hundred flat has 100 small cubes, arranged in 10 rods.
- The digit 7 is worth 100 times more in 700 than in 7.
- The biggest two-digit number is 99, and the smallest three-digit number is 100.
- After the hundreds come the thousands, then ten thousands, then hundred thousands, then millions.
๐ Find out more
๐ Ten make a ten
When we have ten ones, we group them into one rod called a โtenโ. When we have ten tens, we group them into a flat called a โhundredโ. And ten hundreds make a โthousandโ. And so on forever.
๐ The place value chart
We write the number in a chart: the ones column on the right, then the tens, then the hundreds on the left. The number 248 has 2 in the hundreds column, 4 in the tens column and 8 in the ones column.
๐ก Breaking a number apart
We can write a number as a sum: 248 = 200 + 40 + 8. This is called โbreaking the number apartโ, and it helps a lot with mental math.
๐ฏ Zero in a column
If there are no tens, we write a zero in their column: 305 means three hundreds, no tens and five ones. If we forgot the zero we'd write 35, which is a big mistake!
๐ See it in a picture
๐งฎ Worked examples
- 456 = 400 + 50 + 64 hundreds, 5 tens and 6 ones.
- 13 tens = 130Ten tens make a hundred, so thirteen tens = a hundred and thirty.
- 207 = 200 + 7There are no tens, so we write a zero in their column.
๐ Key words
- Ones
- The first column on the right, for single things
- Tens
- The second column, where each one is worth ten
- Place value
- A digit's value according to its place in the number
๐งช Try it at home
Collect 100 matchsticks or straws. Tie them in tens with rubber bands to make bundles. Make the number 47: how many bundles do you need? And how many single sticks?
๐งฉ Test yourself
1 What is the 6 worth in 365?
2 How many tens are in a hundred?
3 Which number has 5 hundreds, 0 tens and 2 ones?