Ten percent of screws produced in a certain factory turn out to be defective. Find the probability that in a sample of 10 screws chosen at random, exactly two will be defective.
- A. 0.2
- B. 0.25
- C. 0.8
- D. 0.3
Answer: A. 0.2
Explanation: Using binomial distribution: P(X = 2) = ¹⁰C₂ × (0.1)² × (0.9)⁸ = 45 × 0.01 × 0.4305 ≈ 0.1937 ≈ 0.2.