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Contributor: Joanna D'Orazio Mignella. Lesson ID: 14128
Discover a fun number trick—writing in expanded form! This skill helps you break down two- and three-digit numbers by place value, making it easier to add them together. Get ready to wow your friends!
Abracadabra! Wow!
It’s pretty amazing how cards can create such exciting surprises! Check out this awesome card trick in the video below.
Just like the magic of cards, you’ll learn how to break down big numbers into smaller parts, making addition a piece of cake!
Jump in!
Card tricks are a lot of fun. So are math tricks!
Put on your magic hat and jump in!
Imagine you've built a giant, colorful block tower. When you build with colorful blocks, you can see each piece clearly and put them together to create a fantastic tower.
You can do the same thing with numbers!
Number Trick 1
You can put numbers together and take them apart. This special number trick is called expanded form.
The expanded form shows each part of a number by breaking it into pieces. When you write numbers in expanded form, place value helps you perform this special trick.
For example, the number 26 can be taken apart in expanded form. When you put it back together, it is 26 again! That's because 20 + 6 = 26.
| tens | ones | ||||||
| 26 | = | 20 | + | 6 |
Like the blocks in the tower, numbers can be taken apart and put back together.
Check out this example for the number 145.
| hundreds | tens | ones | |||||
| 145 | = | 100 | 40 | + | 5 |
Check out this video to see how to use this trick with numbers.
Just like card tricks, numbers can do tricks, too!
Try this trick out with a few numbers. Select the correct expanded form for each number.
Number Trick 2
The expanded form can also help you add numbers together!
When you write numbers in expanded form, you can add them by place value. This number trick will help you add like a math magician!
To add by place value, first, write each number in expanded form.
| 25 | + | 32 | = | |||||
| / | \ | / | \ | |||||
| 20 | + | 5 | 30 | + | 2 | |||
That means 25 + 32 = 57.
Abracadabra! Wow!
Try this number trick: use the expanded form to add by place value with 42 + 17 =?
Wow! You did a fantastic job with this number trick!
You can also add even bigger numbers by place value. Watch the video below to learn how to do this trick!
Great job!
Use this trick to try some more.
Wow!
Now, head to the Got It? section to show off your new number tricks!
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