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  1. Out of 15 students studying in a class, 7 are from Maharastra, 5 are from Karnataka and 3 are from Goa, Four students are to be selected at random. What are the chances that at least one is from Karnataka ?
    1. 12/13
    2. 11/13
    3. 10/15
    4. 1/15
Correct Option: B

Total possible ways of selecting 4 students out of 15 students = 15C4
= (15 x 14 x 13 x 12) / (1 x 2 x 3 x 4) = 1365

The no. of ways of selecting 4 students in which no students belongs to karnataka = 10C4

∴ Number of ways of selecting atleast one student from karnataka = 15C4 - 10C4 = 1155.

∴ Required probability
= 1155 / 1365 = 77 / 91 = 11 / 13



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