Assume that a student’s score in a course follows normal distribution. A sample of 10 students’...

Assume that a student’s score in a course follows normal distribution. A sample of 10 students’ scores is as follow: 65, 32, 78, 90, 45, 66, 78, 55, 24, 87.

(a) Find the sample mean and sample standard deviation for this sample.

(b) Find a 90% confidence interval for the mean score of all the students. Interpret the result.

(c) Test, at significance level 10%, if the average score is lower than 70.

Expert Solution

orchestra answered 2 years ago

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