If the scores for a test have a mean of 100 and a standard deviation of 15, what is the percentage of scores that will fall below 112? Assuming a normal distribution.
To answer this first you will want a z-score, then using either a table or a calculator turn the z-score into a percent.
To calculate a z-score : [your score - mean score] / standard deviation => (112-100)/15 => 12/15 = 0.8
