प्रति प्रश्न समय कैलकुलेटरसूत्र

## How to Calculate Guessing Penalty Impact

When a test penalizes wrong answers, random guessing has an expected value.

### Formula

**Expected Gain = Guesses x (P(correct) x 1 - P(wrong) x Penalty)**

Where P(correct) = 1 / Number of Choices

If the penalty equals 1/(choices-1), guessing has zero expected value.

हल किया गया उदाहरण

A student randomly guesses on 10 questions with 4 choices each and a 0.25 penalty.

  1. P(correct) = 1/4 = 0.25
  2. P(wrong) = 3/4 = 0.75
  3. Expected gain per guess = 0.25 x 1 - 0.75 x 0.25 = 0.25 - 0.1875 = 0.0625
  4. Total expected gain = 10 x 0.0625 = 0.625 points