Scores on an IQ test are normally distributed with a mean of 100 and a standard deviation of 15. What is the z score for an individual whose IQ score was 130?
I'm no expert in Statistics, but I think the z-score is:
z =[ X - M] / S, where X = x-score, M = Mean, S = Standard Deviation. If this is right, then:
z-score =[130 - 100] / 15 = 2