Answer:
Cutoff for a failing score is 49 and 2.28% students failed.
Step-by-step explanation:
We have been given that scores on a psychology exam were normally distributed with a mean of 57 and a standard deviation of 4.
2 standard deviation below mean would be,
Therefore,Cutoff far a failing score is 49.
Now let us find out the z-score for our given values,
Now let us look up the probability from normal distribution table.
Therefore, percentage of students failed is 2.28%.