The standard deviation of a certain group of 1000 high school grade was 11% and the mean grade 78%. Assuming the distribution is normal. Find 1) How many grade were above 90%. 2) What was the highest grade of the lower 10%. 3) What was interquartile range. 4) Within what limits did the middle 90% lie?

The standard deviation of a certain group of 1000 high school grade was 11% and the mean grade 78%. Assuming the distribution is normal. Find 1) How many grade were above 90%. 2) What was the highest grade of the lower 10%. 3) What was interquartile range. 4) Within what limits did the middle 90% lie?

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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The standard deviation of a certain group of 1000 high school grade was 11% and the mean grade 78%. Assuming the distribution is normal. Find

1) How many grade were above 90%.

2) What was the highest grade of the lower 10%.

3) What was interquartile range.

4) Within what limits did the middle 90% lie?

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