November 17, 2010

Sieve of Eratosthenes (located at the National Library of Virtual Manipulatives)

This virtual manipulative displays a grid containing numbers from 2 to 200. You can use it to explore patterns and relationships involving multiples.

Using this virtual manipulative you may:

• Remove multiples of a number
• Show multiples of numbers
• Reset the workspace
• Choose how many rows to display

Prime Factorization - Using the Cake Method

You can use the cake method and prime factorization to find the GCF and LCM

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• The cake method allows you to find the GCF and the LCM at the same time.

Finding the LCM

If there are no common factors then multiply the numbers together (For example: 10 and 3)