A police officer is concerned with excessive speeds on a portion of Interstate 84 with a posted speed limit of 65 miles per hour. Using his radar gun, he records the following speeds for 25 cars and trucks: 82 80 66 71 72 81 76 76 66 68 68 73 74 74 81 82 67 72 73 67 73 74 83 81 77 Click here for the Excel Data File a. Construct a stem-and-leaf diagram. Stem | Leaf b. Are the officer's concerns warranted? Yes
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- The stem values will be 7 and 8, and the corresponding leaf values will be 2, 3, 4, 4, 3, 3. - Arrange the data in ascending order: 72, 73, 73, 74, 74, 83 - Create the stem-and-leaf diagram: 7 | 2 3 3 4 4 8 | 3 Show more…
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The Highway Patrol, using radar, checked the speeds (in mph) of 30 passing motorists at a checkpoint. The results are listed below. 9) Construct a frequency distribution, a relative frequency distribution, and a cumulative frequency distribution using six classes. 10) Construct a frequency histogram, a relative frequency histogram and a frequency polygon using six classes. 11) Construct an ogive using six classes. 12) Construct a stem-and-leaf plot for the data.
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