If you're seeing this message, it means we're having trouble loading external resources on our website.

If you're behind a web filter, please make sure that the domains *.kastatic.org and *.kasandbox.org are unblocked.

Main content

Unit 3: Addition, subtraction, and estimation

1,600 possible mastery points

About this unit

The world of math is full of twists and turns but luckily, this unit on addition, subtraction, and estimation is here to help you navigate. Whether it's mastering the art of rounding or learning how to regroup, Khan Academy is your secret weapon for success.
Level up on the above skills and collect up to 240 Mastery points
Level up on the above skills and collect up to 480 Mastery points
Level up on the above skills and collect up to 400 Mastery points
Level up on the above skills and collect up to 160 Mastery points
Up next for you:

Unit test

Level up on all the skills in this unit and collect up to 1600 Mastery points!