Learn how to solve missing number problems like ___ + 261 = 630.

Practice this lesson yourself on KhanAcademy.org right now:

Watch the next lesson:

Missed the previous lesson?

Grade 3th on Khan Academy: We know you’ve been rocking through 2nd grade adding and subtracting all kinds of whole numbers (up to 2 digits, right?). That’s awesome! In 3rd grade math we want you to start using bigger numbers and start multiplying and dividing, too. By the way, did you know that some numbers aren’t actually “whole?” They’re “partially whole.” We call them fractions! We want you to start playing around and having fun with those, too. There’s also area, perimeter, and place value to be discovered. Whew. We have so much to do and can’t wait to do it with you. Let’s go!

About Khan Academy: Khan Academy offers practice exercises, instructional videos, and a personalized learning dashboard that empower learners to study at their own pace in and outside of the classroom. We tackle math, science, computer programming, history, art history, economics, and more. Our math missions guide learners from kindergarten to calculus using state-of-the-art, adaptive technology that identifies strengths and learning gaps. We’ve also partnered with institutions like NASA, The Museum of Modern Art, The California Academy of Sciences, and MIT to offer specialized content.

## 10 thoughts

1. masvindu says:

Just wanted to point out the typo “3th grade” in the title, with all the video’s you guys post I’m sure it can be easy to miss.

2. The amazing universe says:

hello there Mr. Khan or Sal what r some tips on growing an educational channel?

3. Learn Maths Free says:

Thanks for the video.

4. alrayyaniQtr says:

why I am 17 and watching this?

5. Todd Johnson says:

Good Job.

6. Saron Asmamaw says:

7. Saron Asmamaw says:

or you have a sibling that is in third grade and you want to know what your sibling is doing

8. Nasa P says:

Um Rd not th

9. LuvOrchid Beauty says:

cool

10. Jasmin Trujillo says:

thx