Question
A bag contains 5 brown and 4 white socks. A man pulls out two socks. The probability that these are of the sane colour is.

Answer

  1. $\frac{48}{108}$
Solution:
Total number of balls = 5brown + 4white = 9
Required probability $=\frac{5}{9}\times\frac{4}{8}+\frac{4}{9}\times\frac{3}{8}=\frac{4}{9}$
$\Rightarrow\ \frac{4\times12}{9\times12}=\frac{48}{108}$

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