Historically, the average time it takes Jessica to swim the 200 m butterfly is 148.4 seconds....

Historically, the average time it takes Jessica to swim the 200 m butterfly is 148.4 seconds. Jessica would like to know if her average time has changed. She records her time on 50 randomly selected occasions and computes the mean to be 147.8 seconds. Assume the population standard deviation is 2.2 seconds.

a) Perform the appropriate test of hypothesis to determine whether Jessicas average time has decreased. Use ↵ = 0.05.

Compute the type II error of the test if Jessicas actual mean swimming time is 147.0 seconds. Interpret the results.

i mostly need help with b. (show all your work please) ty

Expert Solution

orchestra answered 2 years ago

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