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The grades on a statistics test are normally distributed with a mean of 62 and Q1=52....

The grades on a statistics test are normally distributed with a mean of 62 and Q1=52. If the instructor wishes to assign B's or higher to the top 30% of the students in the class, what grade is required to get a B or higher?

Please round your answer to two decimal places.

The distribution of scores on a recent test closely followed a Normal Distribution with a mean of 22 points and a standard deviation of 2 points. For this question, DO NOT apply the standard deviation rule.

(a) What proportion of the students scored at least 26 points on this test, rounded to five decimal places?

(b) What is the 23 percentile of the distribution of test scores, rounded to three decimal places?

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orchestra answered 1 year ago
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