According to a recent survey,women chat on their mobile phones more than men (CNN.com,August 25,2010).Irina wants to estimate the difference between the average chat time for female and male college students.She takes a random sample of 40 male students and 40 female students in her college.She finds that female students chatted for a sample average of 820 minutes per month with a sample standard deviation of 160 minutes.Male students,on the other hand,chatted for a sample average of 760 minutes per month with a sample standard deviation of 240 minutes.You may assume that the population variances are equal.
A)Construct a 95% confidence interval for the difference between the population means.
B)Can we conclude that average chat time is different between female and male college students with 95% confidence?

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The Answer of According to a recent survey,women chat on their mobile phones more than men (CNN.com,August 25,2010).Irina wants to estimate the difference between the average chat time for female and male college students.She takes a random sample of 40 male students and 40 female students in her college.She finds that female students chatted for a sample average of 820 minutes per month with a sample standard deviation of 160 minutes.Male students,on the other hand,chatted for a sample average of 760 minutes per month with a sample standard deviation of 240 minutes.You may assume that the population variances are equal.
A)Construct a 95% confidence interval for the difference between the population means.
B)Can we conclude that average chat time is different between female and male college students with 95% confidence?

According to a Recent Survey,women Chat on Their Mobile Phones