Nitin has 8 grey socks and 8 white socks. He pulls two socks randomly without…

2024

Nitin has 8 grey socks and 8 white socks. He pulls two socks randomly without looking at them. What is the probability that both are white?

  1. A.

    1/8

  2. B.

    8/30

  3. C.

    1/2

  4. D.

    7/30

Attempted by 41 students.

Show answer & explanation

Correct answer: D

Answer: 7/30

Method 1 (combinations): Total ways to choose 2 socks from 16 is C(16,2) = 120. Favorable ways to choose 2 white socks from 8 is C(8,2) = 28. Therefore probability = 28/120 = 7/30.

Method 2 (sequential probability): Probability first sock is white = 8/16. Given the first is white, probability the second is white = 7/15. Multiply: (8/16)*(7/15) = 7/30.

Final answer: 7/30

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