According to the 2004 Canadian Community Health Survey,23.1% of Canadians aged 18 or older were considered obese; that is,they had a body mass index (BMI) of 30 or higher.Suppose a current survey in 2014 of 1000 random Canadians found that 245 were obese.Create a 95% confidence interval for the proportion of Canadians that are currently obese.

A) Based on the data,we are 95% confident the current proportion of obese Canadians is between 22% and 24%.
B) Based on the data,we are 95% confident the current proportion of obese Canadians is between 17.97% and 26.03%.
C) Based on the data,we are 95% confident the current proportion of obese Canadians is between 17.97% and 27.03%.
D) Based on the data,we are 95% confident the current proportion of obese Canadians is between 21.8% and 27.2%.
E) Based on the data,we are 95% confident the current proportion of obese Canadians is between 22.44% and 26.56%.

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Joshdeep Thandi · Accepted Answer

Final Answer : D, Explanation :  We can use the formula for a confidence interval for a proportion:CI = p ± z*sqrt((p*(1-p))/n)where p is the sample proportion, z is the z-score corresponding to the desired level of confidence (1.96 for 95% confidence), and n is the sample size.Plugging in the values given:p = 245/1000 = 0.245z = 1.96n = 1000CI = 0.245 ± 1.96*sqrt((0.245*(1-0.245))/1000)CI = 0.245 ± 0.025CI = (0.22, 0.27)Therefore, we can say, with 95% confidence, that the true proportion of obese Canadians is between 21.8% and 27.2%. The best choice is D.

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