Question

One therapy based on classical conditioning for people with phobias is called systematic desensitization. In this therapy people are taught to relax in the presence of stimuli that used to make them respond with fear. In the population it takes an average of 10 sessions for the treatment to work. The standard deviation in the population is 2.37 sessions. Assume that the number of sessions that it takes for the treatment to work follows a normal distribution.

(a) What proportion of people takes 14 or more session to treat their phobias?

(b) What proportion of people takes between 7 and 9 sessions to treat their phobias?

(c) Jordan had a phobia towards cats. He was treated with systematic desensitization and the number of sessions it took him to get rid of his phobia was 2.85 standard deviations above average. How many sessions did it take for Jordan's treatment?

Answer 1