NOTE: A FREE, tiny, low-res version of this lesson is on my web site. Purchase the Video if you want a larger, high quality movie. This lesson consists of giving you the necessary “preliminaries” to do fractions. The tutor explains what are factors, divisors, prime and composite numbers, how to do prime factorization, GCFs, LCMs, multiples, and the rules of divisibility. He also explains how to use your graphing calculator to help you find the GCF, LCM and multiples. Unfortunately, when these videos were made, I used a cheap wireless microphone, so you will hear an occasional “pop” and “buzz” sound when I am talking. I am sorry about this. The disc is not damaged. I have a new microphone now, so new lessons will be of a much higher quality.