Some nations require their students to pass an exam before earning their primary school degrees or domas. A certain nation gives students an exam whose scores are normally distributed with a mean of 41 points and a
standard deviation of 9 points
Suppose we select 2 of these testers at random, and define the random variable D as the deference between
their scores. We can assume that their scores are independent.
Find the probability that their scores are within 10 points of each other
You may round your answer to two decimal places
P (|D| < 10) ≈