SOLUTION: A class has 28 students. There are 5 good students, 13 fairly good students and 10 medium students. Randomly take 4 students to attend the meeting. Find the probability to have at

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Question 388624: A class has 28 students. There are 5 good students, 13 fairly good students and 10 medium students. Randomly take 4 students to attend the meeting. Find the probability to have at least 2 good students that was chosen.
Answer by sudhanshu_kmr(1152) About Me  (Show Source):
You can put this solution on YOUR website!

Total no. of ways to choose 4 students = 28C4
no. of ways to choose at least 2 good students among 4 = 5C2 * 26C2
( 2 from 5 good students and rest 2 from remaining 26 all students)


probability = ( 5C2 * 26C2 ) / 28C4

= 3250 /20475