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### Course: Arithmetic (all content)>Unit 2

Lesson 15: Strategies for adding 2- and 3-digit numbers

# Breaking apart 3-digit addition problems

Sal shows ways to break up addition problems using place value.

## Want to join the conversation?

• Well to break up 4 digit addition problems you do the same process. For example: 4093 + 2056 = 3 ones + 6 ones + 5 tens + 9 tens + 0 hundreds + 0 hundreds + 4 thousands + 2 thousands.

edit: For doing subtraction problems you should probably to carrying witch is kind of similar so yes.
• Why do we have to cross out instead of solving it all in our brains?
• When you solve something in your brain you use all these techniques, even if you don't realize...

Knowing what you are doing and how the numbers work will help you solve problems faster and understand more complex things later
• Why dont you just add 189 + 608?