Exam grades: Scores on a statistics final in a large class were normally distributed with a mean of 74 and a standard deviation of 7. Use the Cumulative Normal Distribution Table to answer the following. (a) What proportion of the scores were above 92? (b) What proportion of the scores were below 66? (c) What is the probability that a randomly chosen score is between 72 and 84? Round answers to at least four decimal places.
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Sri K.
A set of final examination grades in an introductory statistics course is normally distributed, with a mean of 74 and a standard deviation of 8. Complete parts (a) through (d). a. What is the probability that a student scored below 83 on this exam? The probability that a student scored below 83 is 0.8708. (Round to four decimal places as needed.) b. What is the probability that a student scored between 66 and 91? The probability that a student scored between 66 and 91 is (Round to four decimal places as needed.)
The scores on exam 1 were approximately normal with mean of 78 and standard deviation of 7. a) What is the probability that a randomly selected student scored between 71 and 85? 64 and 92? 57 and 99? b) What was the range of scores for the middle: 68%? 95%? 99.7%?
Maitreya E.
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