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42 Chapter 1 %u2022 Analyzing One-Variable Data9. Something fishy As part of a study on salmon health, researchers measured the pH of 25 salmon fillets. 42 Here are the data. Make a stemplot of these data using split stems. 6.34 6.39 6.53 6.36 6.39 6.25 6.45 6.38 6.33 6.26 6.24 6.37 6.32 6.31 6.48 6.26 6.42 6.43 6.36 6.44 6.22 6.52 6.32 6.32 6.48 10. Hot enough for you? Here are the high temperature readings in degrees Fahrenheit for Phoenix, Arizona, for each day in July of a recent year. Make a stemplot of these data using split stems. 111 84 115 108 106 109 111 113 104 103 97 99 104 110 109 100 105 107 102 101 107 93 101 105 99 102 104 108 106 106 109 11. Be still my beating heart! Refer to your stemplot of the heart-rate data from Exercise 7. (a) According to the American Heart Association, a resting pulse rate of less than 60 beats per minute is considered low for this age group. 43 What percentage of these ninth-grade biology students have low resting heart rates by this criterion? (b) Describe the distribution. 12. Beans and protein Refer to your stemplot of the protein content of beans data from Exercise 8. (a) Bean varieties with at least 9 grams of protein per 100 grams of cooked beans are classified as %u201chigh protein.%u201d What percentage of these bean varieties are %u201chigh protein%u201d? (b) Describe the distribution. 13. South Carolina counties Here is a stemplot of the land areas of the 46 counties in South Carolina. 44 Note that the data have been rounded to the nearest 10 square miles ( mi2). 3 68990131115689001155668891336789022369001223674567891011KEY: 6|3 represents acounty with a land area of630 square miles (roundedto the nearest 10 mi2).(a) The smallest data value is for McCormick County. What is its land area? (b) What proportion of South Carolina counties have areas of less than 495 mi2? (c) Describe the shape of the distribution. Are there any outliers? 14. Where are the older folks? Here is a stemplot of the percentage of residents aged 65 and older in the 50%u00a0U.S. states. 45 1112131415161718192018692344445677889999234445579990112225567124773956KEY: 19 | 3 means 19.3% ofthe state%u2019s residents areaged 65 and older.(a) The largest data value is for Maine. What percentage of Maine residents are 65 or older? (Florida has the second largest data value.) (b) In what proportion of states are more than 18% of residents aged 65 and older? (c) Describe the shape of the distribution. Are there any outliers? 15. Jump for the target Will children jump farther if they have a target in front of them? To find out, a gym teacher conducted an experiment with 29%u00a0twelve-yearold children. The teacher wrote the names of all 29 children on identical slips of paper, put them in a hat, mixed them up, and drew out 15 slips. Each of the 15 selected students did a standing long jump from behind a starting line. The remaining 14 students did a similar standing long jump from behind the starting line, but with a target line placed 200 centimeters from the starting line. The distance from the starting line to the back of each student%u2019s closest foot was measured (in centimeters). Here are the data: 46 No target 146 190 109 181 155 167 154 171 157 156 128 157 167 162 137 Target 199 167 147 180 185 170 171 139 154 126 179 158 181 152 (a) Make a back-to-back stemplot to compare the jump distances for the two groups. (b) Are the shapes of the two distributions similar or different? Explain your answer. (c) Do these data provide some evidence that children like the ones in this experiment will jump farther if they have a target in front of them? Justify your answer. 16. Basketball scores Here are the number of points scored by the winning teams in the first round of the National Collegiate Athletic Association (NCAA) Men%u2019s and Women%u2019s Basketball tournaments in a recent year:Men 95 70 79 99 83 72 79 101 69 82 86 70 79 69 69 70 95 70 77 61 69 68 69 72 89 66 84 77 50 83 63 58 Women 80 68 51 80 83 75 77 100 96 68 89 80 67 84 76 70 98 81 79 89 98 83 72 100 101 83 66 76 77 84 71 77 pg 39pg 39%u00a9 Bedford, Freeman & Worth Publishers. For review purposes only. Do not distribute.