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In: Statistics and Probability

     The mean height of a random sample of 47 students who take part in athletic...

     The mean height of a random sample of 47 students who take part in athletic activities at NRDC is 175cm with a standard deviation of 5cm while a random sample of 132 students who showed no interest in athletics had a mean of 170cm and a standard deviation of 7cm.

(a) Construct a 99% confidence interval for the difference in the mean heights of the two groups of students.

(b) Are students who take part in athletic activities taller? Test at the 1% level of significance.

                                                                                                                                                                                                                                                                           

     The mean height of a random sample of 47 students who take part in athletic activities at a school is 175cm with a standard deviation of 5cm while a random sample of 132 students who showed no interest in athletics had a mean of 170cm and a standard deviation of 7cm.

(a) Construct a 99% confidence interval for the difference in the mean heights of the two groups of students.

(b) Are students who take part in athletic activities taller? Test at the 1% level of significance.

                                                                                                                                                                                                                                                                           

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