Review Prime-
First - Watch this video as a review
http://www.khanacademy.org/math/arithmetic/factors-multiples/prime_numbers/v/recognizing-prime-numbers
Next - look over these practice problems:
Factor 42 = 6 * 7 (try to find a prime factor) = 2 *3 * 7
Factor 14 = 2 * 7
Factor 36 = 3 * 12 = 3 * 3 * 4 = 3 * 3 * 2 * 2
Then, watch this video
http://www.khanacademy.org/math/arithmetic/factors-multiples/prime_numbers/v/prime-numbers
Finally, keep practicing...
60 * 10 = 600 * 10 = 6,000 * 10 =
600 * 100 = 6,000 * 100 =
32 * 12 = 31 * 23 =
60 * 10 = 600 * 10 = 6,000 * 10 =
600 * 100 = 6,000 * 100 =
32 * 12 = 31 * 23 =
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