Find P90, the 90th percentile. This is the bone density score separating the bottom 90% from the top 10%. Finding Bone Density Scores. In Exercises 37–40 assume that a randomly selected subject is given a bone density test. Bone density test scores are normally distributed with a mean of 0 and a standard deviation of 1.

In each case, draw a graph, then find the bone density test score corresponding to the given information.