Divisibility Tests for 11 and 13

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Taught by YourMathGal
  • Currently 2.0/5 Stars.
3699 views | 2 ratings
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Lesson Summary:

In this lesson, you will learn two different methods to test if a number is divisible by 11, regardless of its size. The first method involves adding the outside digits and subtracting the middle one, while the second method requires crossing off the last digit and subtracting the remaining digits. You will also learn a method to test if a number is divisible by 13, which involves multiplying the last digit by 4 and adding it to the remaining digits. These tricks are useful for quickly determining the divisibility of large numbers.

Lesson Description:

Goes over two divisibility tests for 11 and also the one for 13.

More free YouTube videos by Julie Harland are organized at http://yourmathgal.com

Questions answered by this video:
  • How can you test a number for divisibility with 11 and 13?
  • How can you tell if a number is divisible by 11 or 13?
  • How can you tell if a number is a factor of another number without having to do division?
  • What are the tests for divisibility?
  • How can you tell if a number is divisible by 11?
  • How do you know if 11 goes into a number?
  • How can you tell if a number is divisible by 13?
  • How do you know if 13 goes into a number?
  • What is the trick / test for figuring out if 11 goes into a number without dividing?
  • How can you tell if 11 goes into a 6-digit number?
  • How can you tell if 108064 is divisible by 11?
  • How can you tell if 78231 is divisible by 11?
  • How can you tell if 314926 is divisible by 11?
  • What are the two tests for determining whether 11 is a factor of a multi-digit number?
  • What is the trick / test for figuring out if 13 goes into a number without dividing?
  • How can you tell if 7566 is divisible by 13?
  • How can you tell if 7405 is divisible by 13?
  • Staff Review

    • Currently 4.0/5 Stars.
    This lesson shows multiple examples of easy tricks / tests for determining if large numbers are divisible by 11 or 13. All steps are explained in this very understandable lesson. This is a great way to check for divisibility without a calculator.