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There are n socks in a drawer, of which 3 socks are red. If 2 of the socks are chosen randomly and the probability that both selected socks are red is 1 2 , then what is the value of n ?

Options

  1. A3
  2. B4
  3. C5
  4. D6

Correct answer

B. 4

Step-by-step solution

Number of socks = n Number of red socks =3 Given, ^3 C₂ ^n C₂ = 1 2 aligned & ^n C₂=3 2=6 & n=4 aligned

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