Khan Academy

Khan Academy

Arithmetic

The most basic of the math playlists. Start here if you have very little background in math fundamentals (or just want to make sure you do). After watching this playlist, you should be ready for the pre-algebra playlist.

1. Basic Addition
2. Addition 2
3. Level 2 Addition
4. Addition 3
5. Addition 4
6. Basic Subtraction
7. Subtraction 2
8. Subtraction 3: Introduction to Borrowing or Regrouping
9. Alternate mental subtraction method
10. Level 4 Subtraction
11. Why borrowing works
12. Adding Decimals
13. Subtracting decimals
14. Basic Multiplication
15. Multiplication 2: The Multiplication Tables
16. Multiplication 3: 10,11,12 times tables
17. Multiplication 4: 2-digit times 1-digit number
18. Multiplication 5: 2-digit times a 2-digit number
19. Multiplication 6: Multiple Digit Numbers
20. Multiplication 7: Old video giving more examples
21. Mulitplication 8: Multiplying decimals (Old video)
22. Lattice Multiplication
23. Why Lattice Multiplication Works
24. Division 1
25. Division 2
26. Division 3: More long division and remainder examples
27. Level 4 division
28. Converting fractions to decimals
29. Percent and decimals
30. Dividing decimal
31. Ordering numeric expressions
32. Greatest Common Divisor
33. Least Common Multiple
34. Equivalent fractions
35. Mixed numbers and improper fractions
36. Time Differences 1
37. Time Differences in Different Time Zones
38. Prime N

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