"Discrete mathematics and computer science,"
	Basic Probability, Permutations, and Combinations - Christopher Di Antonio, Century High School
	Probability, the calculation of the likelihood of an event, is a recent development in mathematics; and it is in our everyday lives. Whether we are playing cards, rolling dice, playing the lottery or in Las Vegas encountering all sorts of games, probability surrounds us. Probability almost always determines outcomes. Pascal and Fermat first discovered mathematical probability in the seventeenth century, three hundred fifty years ago. Probability involves determining the likelihood of random events over the long run. When a couple conceives a child we cannot be sure, without tests, whether the baby will be a boy or a girl. What we can say is over the long-run 51.2 % of all live births are boys. In this unit of curriculum we want to expand the student's understanding of probability through representations. These representations make probability understandable and lead to some important policy issues and applications. We will introduce and develop notations and formulas for combinations and permutations and a sense of when various counting strategies are applicable. It is the strategies and problem solving skills that are of real value when dealing with probability. Upon completion of the unit the student will be able to (1) solve problems related to the basic counting principle, (2) distinguish between dependent and independent events, (3) solve problems involving permutations, and (4) solve problems involving combinations. The material developed here may be taught as a complete unit in Algebra 2 classes or in some form as an introduction to middle school and high school mathematics courses.