Consider columns 1 and 3 of the energy consumption data given in Exercise 224

# Consider columns 1 and 3 of the energy consumption

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2.80Consider columns 1 and 3 of the energy-consumption data given in Exercise2.24.Compute the midpoint for each class presented in column 1.Pair eachmidpoint with its corresponding relative frequency found in column 3.Construct a horizontal axis, where the units are in terms of midpoints and avertical axis where the units are in terms of relative frequencies.Foreach midpoint on the horizontal axis, plot a point whose height is equal tothe relative frequency of the class.Then join the points with connectinglines.The result is a relative-frequency polygon. Full file at 46 Chapter 2, Descriptive Statistics 2.81 (a)Consider all three columns of the energy-consumption data given inExercise 2.24. (b)Pair each cutpoint in reworked column 1 with its correspondingcumulative relative frequency found in reworked column 3.Construct ahorizontal axis, where the units are in terms of the cutpoints and avertical axis where the units are in terms of cumulative relativefrequencies.For each cutpoint on the horizontal axis, plot a pointwhose height is equal to the cumulative relative frequency.Then jointhe points with connecting lines.The result, presented in Figure(b), is anogiveusing cumulative relative frequencies.(Note: Asimilar procedure could be followed using cumulative frequencies.) Residential Energy Consumption 0.00 0.05 0.10 0.15 0.20 0.25 35 45 55 65 75 85 95 105 115 125 135 145 155 165 BTU (Millions) Relative Frequency Full file at Section 2.3, Graphs and Charts 47 Residential Energy Consumption 0 0.2 0.4 0.6 0.8 1 1.2 20 30 40 50 60 70 80 90 10 0 11 0 12 0 13 0 14 0 15 0 16 0 BTU (Millions) Cumulative Relative Frequency 2.82 (a) After rounding each weight to the nearest integer (Any weight ending in .5 is rounded up.), the stem-and-leaf diagram for the rounded weights is 12 9 13 27 14 366 15 011599 16 12567 17 003445689 18 235789 19 1 20 9 21 58 22 23 24 25 26 27 9 (b) After truncating each weight, the stem-and-leaf diagram for the rounded weights is 12 9 13 26 14 2569 15 01588 16 11557 17 002335588 18 225778 19 1 20 9 21 48 22 23 24 25 26 27 8  #### You've reached the end of your free preview.

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