Dr Patton is a professor of English Recently she counted the

Dr Patton is a professor of English. Recently she counted the number of misspelled words in a group of student essays. She noted the distribution of misspelled words per essay followed the normal distribution with a population deviation of 2.44 words per essay. For her 10 A.M. section of 40 students, the mean number of misspelled words was 6.05. Construct a 90 percent confidence interval for the mean number of misspelled words in the population of student essays.

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