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數學與統計 大學

急!求救 #6 8 9 如果需要酬勞可私下談 (ex.$70題)

pie participation in informal 6.The National Science Foundation (NSF) sponsored a study on girls' science, technology, engineering, or mathematics (STEM) programs. The results of the study were published in Cascading Influences: Long-Term Impacts of Informal STEM Experiences for Girls (March 2013). The researchers sampled 174 young women who recently participated in a STEM program. They used a pie chart to describe the geographic location (urban, suburban, or rural) of the STEM programs attended. Of the 174 participants, 107 were in urban areas, 57 in suburban areas, and 10 in rural areas. a.Determine the proportion of STEM participants from urban areas. b.Determine the proportion of STEM participants from suburban areas. c.Determine the proportion of STEM participants from rural areas. d. Multiply each proportion in parts a-c by 360 to determine the pie slice size (in degrees) for each location. e.Use the results, part d, to construct a pie chart for geographic location of STEM participants. f.Interpret the pie slice for urban areas. g.Convert the pie chart into a bar graph. Which, in your opinion, is more informative? 7. All high way bridges in the US are inspected periodically for structural deficiency by the FHWA. Data from the FHWA inspections are compiled into the National Bridge Inventory (NBI). Classify each variable below as quantitative or qualitative. a. Length of maximum span (feet). b. Number of vehicle lanes. c. Toll bridge (yes or no). d. Average daily traffic. e. Condition of deck (good, fair, or poor). f. Bypass or detour length (miles). g. Route type (interstate, U.S., state, county, or city) 8. The NBI data were analyzed and the results made available at the FHWA Web site. Using the FHWA inspection ratings, each of the 608,272 highway bridges in the US was categorized as structural deficient, functionally obsolete, or safe. About 13.5% of the bridges were found to be structural deficient, while 3.5% were functionally obsolete. a. What is the variable of interest to the researchers? b. Is the variable of part a quantitative or qualitative? c. Is the data set analyzed a population or a sample? Explain. d. How did the NBI obtain the data for the study?

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數學與統計 大學

數學/統計學/共變異數/相關係數 想請問一下題目上的第三題要如何求算ಥ_ಥ (網路上查到的題型都是實數對實數,這裡是給一個範圍⋯而且求的是開架跟天數而不是兩區的差別) 附上上課給的範例嗚嗚嗚 麻煩了ಥ_ಥ謝謝各位

Question 2 (125) V2 某家位於美國中部小鎮之小型房地產仲介,現想瞭解物件自委託到買賣成立所需的時間。該 公司分析近近三年來成交的 800 筆資料,整理如下表。 成交所需天數 30 天以內 31-90 天 90 天以上 總和 $150,000 以下 50 40 10 100 6 6:125 $150,000-$199,999 20 150 開價 80 250 0,3125 $200,000-$250,000 20 280 100 400 05 $250,000 以上 10 30 10 50 總和 100 500 200 800 如果該公司簽下委賣合約,開價在$150,000 以下,則成交天數在90 天以下的機率 為何? b. 如果事件 A表示成交所需天數在90天以上,事件B表示開價在$150,000 以下, 請問事件A與B 是否為獨立事件?試說明之。 C. 假設該公司將800 筆數據又細分為東區及西區(兩區房價分佈相似),並統計在售價 區間的平均銷售天數,其結果呈現如下表。試算共變異數及相關系數,說明開價與平 均銷售天數有甚麼關係。 平均銷售成所需天數 0,0625 a. 東區 西區 PC62 37 42 54 66 開價 $150,000 以下 $150,000-$199,999 $200,000-$250,000 $250,000 以上 71 82 46 50 出S(新) 法制度信天名之戈登发 才有哪 and AND cing 0 .action 2 (104)

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