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Milwaukee. Develop a frequency table and a relative frequency table to summarize thisinformation.5.Wellstone, Inc., produces and markets replacement covers for cell phones in a variety ofcolors. The company would like to allocate its production plans to five different colors:bright white, metallic black, magnetic lime, tangerine orange, and fusion red. The com-pany set up a kiosk in the Mall of America for several hours and asked randomly selectedpeople which cover color was their favorite. The results follow:Constructing Frequency Distributions: Quantitative DataIn Chapter 1 and earlier in this chapter, we distinguished between qualitative andquantitative data. In the previous section using the Whitner Autoplex data, we sum-marized the qualitative variable, vehicle type, using a frequency table, a relative fre-quency table, a bar chart, and a pie chart.The Whitner Autoplex data also includes two quantitative variables: selling priceand age of the buyer. Suppose Ms. Ball wants to summarize last month’s sales usingselling price. We can describe selling price using a frequency distribution.How do we develop a frequency distribution? The first step is to tally the data intoFREQUENCY DISTRIBUTIONA grouping of data into mutually exclusive classes showing the number of observations in each class.
28Chapter 2ExampleSolutionStep 1: Decide on the number of classes.The goal is to use just enoughgroupings or classesto reveal the shape of the distribution. Some judg-ment is needed here. Too many classes or too few classes might notreveal the basic shape of the data set. In the vehicle selling price exam-ple, three classes would not give much insight into the pattern of thedata (see Table 2–5).We return to the situation where Ms. Kathryn Ball of AutoUSA wants tables, charts,and graphs to show the typical selling price on various dealer lots. Table 2–4 reportsonly the price of the 80 vehicles sold last month at Whitner Autoplex. What is thetypicalselling price? What is the highestselling price? What is the lowestsellingprice? Around what value do the selling prices tend to cluster?TABLE 2–4Prices of Vehicles Sold Last Month at Whitner AutoplexHighestLowest$23,197$23,372$20,454$23,591$26,651$27,453$17,26618,02128,68330,87219,58723,16935,85119,25120,04724,28524,32424,60928,67015,546 15,93519,87325,25125,27728,03424,53327,44319,88920,00417,35720,15519,68823,65726,61320,89520,20323,76525,78326,66132,27720,64221,98124,05225,79915,79418,26335,92517,39917,96820,35621,44221,72219,33122,81719,76620,63320,96222,84526,28527,89629,07632,49218,89021,74022,37424,57125,44928,33720,64223,61324,22030,65522,44217,89120,81826,237