Question

In a class of 777, there are 333 students who have done their homework.

If the teacher chooses 333 students, what is the probability that none of the three of them have done their homework?

Answer 1

5/12

Explanation:

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Answer 2

4/35

Explanation:

The probability that the teacher will choose someone who has not done his homework is the number of students who have not done their homework divided by the total number of students: 4/7

So, the probability that the teacher picks a second student who also has not done his homework is 3/6

So, the probability of the teacher picking 3 students such that none of them have done their homework is 4/7×3/6×2/5=24/210=4/35

Hope this helps.