The scores out of 50 points on a recent vocabulary test for all of the 120 students enrolled in a statistics class at a local high school is approximately normally distributed with a mean of 34.82 points and a standard deviation of 5.02 points. The teacher plans to select a random sample of 6 students to survey about how to increase student performance on the next vocabulary test. a. Calculate the mean and standard deviation of the sampling distribution of , the sample mean number of points scored by students for samples of size n = 6. b. Interpret the standard deviation of the sampling distribution calculated in part (a). c. The teacher believes that if a student scored less than 30 points, the student will have a different opinion than if a student scored more than 30 points. Calculate the probability that in a random sample of 6 students, the sample average would be less than 30 points.

The scores out of 50 points on a recent vocabulary test for all of the 120 students enrolled in a statistics class at a local high school is approximately normally distributed with a mean of 34.82 points and a standard deviation of 5.02 points. The teacher plans to select a random sample of 6 students to survey about how to increase student performance on the next vocabulary test. a. Calculate the mean and standard deviation of the sampling distribution of , the sample mean number of points scored by students for samples of size n = 6. b. Interpret the standard deviation of the sampling distribution calculated in part (a). c. The teacher believes that if a student scored less than 30 points, the student will have a different opinion than if a student scored more than 30 points. Calculate the probability that in a random sample of 6 students, the sample average would be less than 30 points.

MATLAB: An Introduction with Applications

6th Edition

ISBN:9781119256830

Author:Amos Gilat

Publisher:Amos Gilat

Chapter1: Starting With Matlab

Section: Chapter Questions

Problem 1P

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