Suppose the average client charge per hour for out-of-court work by lawyers in the state of Iowa is $125. Suppose further that a random telephone sample of 32 lawyers in Iowa is taken and that the sample average charge per hour for out-of-court work is $110. If the population variance is $525, what is the probability of getting a sample mean of $110 or larger? What is the probability of getting a sample mean larger than $135 per hour? What is the probability of getting a sample mean of between $120 and $130 per hour?
Added by Amy S.
Step 1
First, we need to find the standard error (SE) of the sample mean. The standard error is given by the formula: SE = \frac{\sigma}{\sqrt{n}} where σ is the population standard deviation and n is the sample size. Since the population variance is given as $525, the Show more…
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