# Question: Twenty four 9th and 10th grade high school girls were put on

Twenty-four 9th- and 10th-grade high school girls were put on an ultra-heavy rope-jumping program. The following data give the time difference for each girl (“before program time” minus “after program time”) for the 40-yard dash:

(a) Give a point estimate of μD, the mean of the difference in race times.

(b) Find a one-sided 95% confidence interval that is a lower bound for μD.

(c) Does it look like the rope-jumping program was effective?

(a) Give a point estimate of μD, the mean of the difference in race times.

(b) Find a one-sided 95% confidence interval that is a lower bound for μD.

(c) Does it look like the rope-jumping program was effective?

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