Question 680956
A professor grading a statistics examination has promised to give an equal number of A's, B's, C's, and D's. If three students are chosen randomly, what is the probability that all three will receive different grades?
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If there are 4 students:
The 1st choice can be any grade.
The 2nd is one of 3
The 3rd is one of 2
1/3 * 1/2 = 1/6
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