Members of fraternities and sororities are required to volunteer for community service. Do fraternity brothers work more volunteer hours on average than sorority sisters? The data below show the number of volunteer hours worked for twelve randomly selected fraternity Brothers and twelve randomly selected sorority sisters. Brothers: 8 8 5 3 12 5 14 12 11 9 14 10 Sisters: 9 5 7 8 5 4 6 9 5 6 3 8 сл

Bicycling, the world's leading cycling magazine, reviews hundreds of bicycles throughout the year. Their "Road-Race" category contains reviews of bikes used by riders primarily interested in racing. One of the most important factors in selecting a bike for racing is the weight of the bike. The following data show the weight (pounds) and price ($) for 10 racing bikes reviewed by the magazine.† Brand Weight Price ($) FELT F5 17.8 2,100 PINARELLO Paris 16.1 6,250 ORBEA Orca GDR 14.9 8,370 EDDY MERCKX EMX-7 15.9 6,200 BH RC1 Ultegra 17.2 4,000 BH Ultralight 386 13.1 8,600 CERVELO S5 Team 16.2 6,000 GIANT TCR Advanced 2 17.1 2,580 WILIER TRIESTINA Gran Turismo 17.6 3,400 SPECIALIZED S-works Amira SL4 14.1 8,000 (a) Use the data to develop an estimated regression equation that could be used to estimate the price for a bike given the weight. (Round your numerical values to the nearest integer). ŷ = ??       (b) Compute r2. (Round your answer to three decimal…

Suppose Laura, a facilities manager at a health and wellness company, wants to estimate the difference in the average amount of time that men and women spend at the company's fitness centers each week. Laura randomly selects 15 adult male fitness center members from the membership database and then selects 15 adult female members from the database. Laura gathers data from the past month containing logged time at the fitness center for these members. She plans to use the data to estimate the difference in the time men and women spend per week at the fitness center. The sample statistics are summarized in the table. Population Populationdescription Population mean(unknown) Samplesize Sample mean(min) Sample standarddeviation (min) 11 male μ1 n=15 x¯1=137.7 s=51.7 22 female μ2 n=15 x¯2=114.6 s=34.2   df=24.283   The population standard deviations are unknown and unlikely to be equal, based on the sample data. Laura plans to use the two-sample ?-t-procedures to estimate the…

Suppose the prevalence of "dance fever" at a college is 40% among women and 10% among men. If there are half as many men as women, what is the overall prevalence of dance fever at the college? What proportion of people without dance fever at that college are women?