SAMPLE College Math
Suppose Emily, who resides incityA,wishestogotocityCviacityB.Itisknownthattherearethree differentroutesbetweencityAandB,andthentherearetwodifferentroutesbetweencityBandC.Now we have to calculate how many options does Emily have? Let us understand this by drawing a tree diagram. Tree diagram refers to the graphical representation of all possible outcomes.
Intheabovecase,EmilyhasatotalofsixoptionstotravelfromcityAandCityCviacityB,thataread, ae,bf,bg,ch,andci.Hence,thereareatotalofsixoptions.Itwillbetoughtocountthetotalpossibilities if the sample space is much higher. Sample space refers to the set of all possible outcomes. B. Fundamental Counting Principle Ifoneeventoccursinmways,andanothereventoccursinnwaysaftertheoccurrenceofm,thenthe total number of ways in which the two events can occur is calculated as m X n ways. In the above example,EmilycantravelbetweencityAandcityBinthreepossibleways,andthenumberofwaysin which between city B and C istwo.Applyingthefundamentalcountingprinciple,thetotalnumbersof ways in which Emily can travel are 3 * 2 = 6 ways. Let us take a few more examples to gain expertise in the concept. Remember the Cocoberry Frozen Yogurtofferingthechoiceof6baseflavorsofyogurtand12optionsoftoppings?Wecancalculatethe totalnumberofpossibilitiesofdifferentyogurtsfromthestoreusingthecountingprinciple.Inthiscase, m = 6 and n = 12. Thus, we can say that there are 6*12 = 72 ways of selectingthefrozenyogurtat Cocoberry. Now,letusconsideranexamplewithabiggersamplespace.Inacountry,theautomobilesbearlicense plates with a combination of different letters and digits, such that the initial 2 positions are filled by letters and then the last three positions are taken by single digits. Now, what is the total number of possibilities of different license plates be made out of this? Weknowthat,thereare26letters(AtoZ)andatotalof10digits(from0to9).Thenumberofwaysin which first position of the licenseplatecanbefilledis26,thesecondpositioncanalsobefilledin26 ways,thethirdin10,thefourthin10,andthefifthpositionin10ways.Hence,thetotalnumberofways the license plate can be made is:
© 2023 ACHIEVE ULTIMATE CREDIT-BY-EXAM GUIDE|COLLEGE MATH
54
Made with FlippingBook - Online Brochure Maker