Question

Problem 8. (1 point) Suppose the scores of students on a Statistics course are Normally distributed with a mean of 261 and a standard deviation of 66 What percentage of the students scored between 261 and 391 on the exam? (Give your answer to 3 significant figures) I percent.

Answer 1

Here it is given that distribution is normal with mean=261 and standard deviation=65

We need to find $P(261<x<391)$

As distribution is normal we can convert x to z

$P(261<x<391)=P(\frac{261-261}{65}<z<\frac{391-261}{65})=P(0<z<2)=0.4772$

Hence answer here is 47.720%