In the Global Youth Tobacco Survey, conducted jointly by the World Health Organization and the US Centers for Disease Control and Prevention (CDC), a random sample of children aged 13 15 in various cities around the world were interviewed to determine the percentage of children in this age group who smoke cigarettes. Among the results for boys in samples taken in major South American cities, the study reported: Buenos Aires, Argentina (21.9% smoke, sample size = 475); Bogota, Colombia (31.0% smoke, sample size = 700); Santiago, Chile (31.3% smoke, sample size = 350) (cdc.gov/tobacco/). Use the chi square test of proportion differences to test the hypothesis that the proportion of boys in this age group who smoke is the same for all three cities. Use a significance level of 5%.