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In: Statistics and Probability

Scores on a statistics final in a large class were normally distributed with a mean of...

Scores on a statistics final in a large class were normally distributed with a mean of 71 and a standard deviation of 8. Use the Cumulative Normal Distribution Table to answer the following.

(a) Find the 30th percentile of the scores.

(b) Find the 70th percentile of the scores.

(c) The instructor wants to give an A to the students whose scores were in the top 5 % of the class. What is the minimum score needed to get an A?

(d) Between what two values is the middle 60 % of the scores? Round the answers to at least two decimal places.

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