Lesson 2.1 · Place Value to 1,000
Hundreds, tens and ones
You already know that 10 ones make 1 ten. Now numbers get bigger. When you have 10 tens, you can bundle them into 1 hundred. That lets you read numbers all the way up to 1,000.
Make a hundred
In this lesson, we use three kinds of blocks:
- 🟧 is 1 one.
- 🟦 is 1 ten (a stick of 10 ones).
- 🟪 is 1 hundred (a flat of 10 tens).
Count by tens ten times: 10, 20, 30, 40, 50, 60, 70, 80, 90, 100. So 10 tens is 100.
10 tens = 1 hundred
10 ones make 1 ten. 10 tens make 1 hundred. And 10 hundreds make 1 thousand, which we write as 1,000.
Three-digit numbers
A three-digit number has three places.
Definition
Hundreds, tens and ones
In a three-digit number, the left digit tells how many hundreds. The middle digit tells how many tens. The right digit tells how many ones.
| Hundreds | Tens | Ones |
|---|---|---|
| 2 | 4 | 7 |
The number 247 has 2 hundreds, 4 tens and 7 ones.
Worked example: Count the blocks
What number is this?
🟪🟪🟪
🟦🟦
🟧🟧🟧🟧
There are 3 hundreds, 2 tens and 4 ones. Count the hundreds: 100, 200, 300. Count on the tens: 310, 320. Count on the ones: 321, 322, 323, 324. The number is 324.
Worked example: What does each digit mean?
In 586, what is the value of the 8?
The 8 is in the tens place. 8 tens is 80. So the 8 is worth 80.
Worked example: A zero in the middle
What number has 4 hundreds, 0 tens and 9 ones?
Put 4 in the hundreds place, 0 in the tens place and 9 in the ones place. The number is 409.
Common mistake
Don't skip the zero! 4 hundreds and 9 ones is 409, not 49. The 0 holds the tens place so the 4 stays in the hundreds place.
Tip
The same digit can be worth different amounts. In 333, the first 3 is worth 300, the next 3 is worth 30, and the last 3 is worth 3.
Practice
What number is this?
🟪🟪
🟦
🟧🟧🟧
Type a number.
How many hundreds are in 658?
Type a number.
Fill in the blank: 712 has 7 hundreds, ___ tens and 2 ones.
Type a number.
What number has 8 hundreds, 3 tens and 5 ones?
Type a number.
What is the value of the 7 in 471?
Type a number.
What number has 6 hundreds, 0 tens and 2 ones?
Type a number.
Which one means the same as 1 hundred?
Sam has 3 boxes of 100 stickers and 4 packs of 10 stickers. He has no loose stickers. How many stickers does he have?
Type a number.