In: Statistics and Probability
The question was:
Finals are over and the marks are in. For all the students who have completed the introductory course to business statistics the distribution of the grades represented a bell-shaped distribution, symmetrical about the average which was 75.90 marks. The standard deviation was 1.40.
Given the information above, answer the following questions using the Empirical Rule.
For full marks your answer should be accurate to at least two
decimal places.
a) Approximately what percentage of marks were above 77.30?
b) Approximately what percentage of marks were below 71.70?
c) Approximately what percentage of marks were between 71.70 and 80.10?
I don't want to get answers, I want method steps,Thanks!
Please rate. Thanks !!!
By solving empirically, difference is that we do not use z table for probabilities rather we use 68-95-99.7 rule to calculate probabilities. Rest procedure will remain same.
I have solved both actual and empirically for better understanding.
Solved empirically - follows