Question

A bag contains 5 brown and 4 white socks. A man pulls out 2 socks. Find the probability that they are of the same colour.

• A. \(\dfrac{4}{9}\)
• B. \(\dfrac{2}{9}\)
• C. \(\dfrac{5}{9}\)
• D. \(\dfrac{7}{9}\)

Hint:

For “same colour”, add probabilities of each colour case.

Answer 1

The Correct Option is A

Step 1: Total ways: \[ {}^9C_2=36 \]
Step 2: Same colour socks: \[ {}^5C_2+{}^4C_2=10+6=16 \]
Step 3: \[ P=\frac{16}{36}=\frac{4}{9} \]