Lesson 2.2 · Place Value to 1,000
Expanded form and number names
There is more than one way to write a number. You can write it with digits, break it into parts, or spell it with words. Each way shows the same amount.
Expanded form
Take 365. It has 3 hundreds, 6 tens and 5 ones. Write the value of each digit and add them up.
Definition
Expanded form
Expanded form writes a number as the sum of the values of its digits. The standard form is the usual way, with just digits: 365.
If a digit is 0, it is worth nothing, so you can leave it out. .
Number names
The number name is the number written in words. Read the hundreds, then the rest.
| Standard form | Expanded form | Number name |
|---|---|---|
| 365 | 300 + 60 + 5 | three hundred sixty-five |
| 508 | 500 + 8 | five hundred eight |
| 740 | 700 + 40 | seven hundred forty |
| 219 | 200 + 10 + 9 | two hundred nineteen |
Say the hundreds, then the tens and ones
Say the hundreds digit and the word "hundred." Then read the last two digits like a two-digit number. For 472, say "four hundred" and then "seventy-two."
Worked example: Write in expanded form
Write 847 in expanded form.
The 8 is worth 800. The 4 is worth 40. The 7 is worth 7. So .
Worked example: From words to digits
Write "six hundred three" with digits.
Six hundred is 6 hundreds. There are no tens. "Three" is 3 ones. So the number is 603.
Worked example: Parts in a new order
What number is ?
Find each place. 200 is 2 hundreds. 90 is 9 tens. 5 is 5 ones. The number is 295.
Common mistake
Don't just stick the words together as digits. "Four hundred twelve" is 412, not 40012. There are only three places: hundreds, tens and ones.
Practice
Fill in the blank:
Type a number.
What number is ?
Type a number.
Fill in the blank:
Type a number.
Write "two hundred eight" with digits.
Type a number.
Which is the number name for 350?
Which is 704 in expanded form?
Write "eight hundred sixteen" with digits.
Type a number.
What number is ?
Type a number.