Suppose the heights of fully grown pine trees in the state of Washington have mean 67 ft and standard deviation 1.05 ft. A) Is a sample of size 30 or more required to obtain a normally distributed sampling distribution of mean heights. Yes No Correct B) What is the probability that the mean height of 31 fully grown trees selected at random is between 66.5 and 67.5 feet tall? (Round σx¯ to two decimal places and your answer to four decimal places.)
Added by Andrew S.
Step 1
- Population mean, \(\mu = 67\) ft - Population standard deviation, \(\sigma = 1.05\) ft - Sample size, \(n = 31\) - Interval for sample mean: between 66.5 and 67.5 ft --- Part A Show more…
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