검증된 단계별 안내
04:51
05:45
04:48Use the data set and the indicated number of classes to construct
(c) a frequency polygon,
Hospitals
Number of classes: 8
Data set: Number of hospitals in each of the 50 U.S. states and 5 inhabited territories (Source: American Hospital Directory) 10 90 51 1 77 341 56 34 8 214 111 3 14 40 18 142 102 55 75 108 72 53 19 105 55 83 1 69 19 108 10 27 14 78 37 31 186 146 90 37 177 52 11 67 25 100 361 35 91 2 7 61 78 33 14
Use the ogive to approximate the
the number of black bears that weigh between 158.5 pounds and 244.5 pounds.
What Would You Do? You work at a bank and are asked to recommend the amount of cash to put in an ATM each day. You do not want to put in too much (which would cause security concerns) or too little (which may create customer irritation). The daily withdrawals (in hundreds of dollars) for 30 days are listed. 72 84 61 76 104 76 86 92 80 88 98 76 97 82 84 67 70 81 82 89 74 73 86 81 85 78 82 80 91 83
If you are willing to run out of cash on 10% of the days, how much cash should you put in the ATM each day? Explain.
Studying Refer to the data set in Exercise 23 and the box-and-whisker plot you drew that represents the data set.
c. You randomly select one student from the sample. What is the likelihood that the student studied less than 2 hours per day? Write your answer as a percent.
Pearson’s Index of Skewness The English statistician Karl Pearson (1857–1936) introduced a formula for the skewness of a distribution.
P = 3 (x̄ - median) / s
Most distributions have an index of skewness between -3 and 3. When P > 0, the data are skewed right. When P < 0, the data are skewed left. When P = 0, the data are symmetric. Calculate the coefficient of skewness for each distribution. Describe the shape of each.
c. x̄ = 9.2, s = 1.8, median = 9.2
Use the frequency histogram
describe any patterns with the data..
