SOLUTION: The scores on a psychology exam were normally distributed with a mean of 62 and a standard deviation of 7. A failing grade on the exam was anything 2 or more standard deviations be
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Question 1155574: The scores on a psychology exam were normally distributed with a mean of 62 and a standard deviation of 7. A failing grade on the exam was anything 2 or more standard deviations below the mean. What was the cutoff for a failing​ score? Approximately what percentage of the students​ failed ? Answer by Boreal(15235) (Show Source):
You can put this solution on YOUR website! Failing would be more than 2 sd s below the mean or more than 14 points.
Failing score would be below 62-14 or 48, which is the cutoff score. Approximately 2.5 per cent of the students fail, since there are 95% interval in the middle leaving 2.5% at each end. Only one end fails, however.