Probability 40131
There are 28 students in the IK3 class. Three pupils will be examined. Nineteen pupils are ready for the exam. What is the probability that all three will be unprepared?
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Math student
This is incorrect as it assumes a constant probability as the kids are chosen. The answer would be 9/28 * 8/27 * 7/26 OR 9C3 / 28C3.
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