CA Foundation · Quantitative Aptitude · Probability
A game costs ₹50 to play. Two fair coins are tossed and the player receives ₹40 for each head that appears. What is the expected net gain of the player per game?
The expected net gain is -₹10. The expected number of heads in two tosses is 1, so the expected receipt is ₹40, which is ₹10 less than the ₹50 fee paid to play.
- A-₹10Correct
- B-₹30
- C₹0
- D₹10
Explanation
Expected number of heads = 2 × 0.5 = 1, so expected receipt = 40 × 1 = ₹40. Net gain = 40 - 50 = -₹10. Check by distribution: 0 heads (1/4) gives 0, 1 head (1/2) gives 40, 2 heads (1/4) gives 80; expected = 0+20+20 = 40. A game with zero expectation would need a ₹40 fee, so ₹0 is wrong.
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