Question: Dental Anxiety Scale. Psychology students at Wittenberg University completed the Dental Anxiety Scale questionnaire (Psychological Reports, August 1997). Scores on the scale range from 0 (no anxiety) to 20 (extreme anxiety). The mean score was 11 and the standard deviation was 3.5. Assume that the distribution of all scores on the Dental Anxiety Scale is normal with μ = 11 and σ = 3.5.
(a) Suppose you score a 16 on the Dental Anxiety Scale. Find the z-value for this score.
(b) Find the probability that someone scores between a 10 and a 15 on the Dental Anxiety Scale.
(c) Find the probability that someone scores above a 17 on the Dental Anxiety Scale.