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Exam grades: Scores on a statistics final in a large class were normally distributed with a...

Exam grades: Scores on a statistics final in a large class were normally distributed with a mean of

70 and a standard deviation of 10. Use the TI-84 PLUS calculator to answer the following. Round the answers to at least two decimals.

(a) Find the 42nd percentile of the scores.

(b) Find the 71st percentile of the scores.

(c) The instructor wants to give an A to the students whose scores were in the top 10% of the class. What is the minimum score needed to get an A?

(d) Between what two values are the middle 68% of the scores? (Enter the smaller number in the first box.)

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Expert Solution

orchestra answered 1 year ago
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