A random variable X has probability density function f(x) = 1/6 for 0 ≤ x ≤ 6 and f(x) = 0 otherwise. What is P(2 ≤ X ≤ 5)?
Correct answer: B. 1/2
- A. 1/6
- B. 1/2
- C. 2/3
- D. 5/6
Explanation
The density is constant, so the probability equals the interval length multiplied by the density. Hence P(2 ≤ X ≤ 5) = (5 − 2)(1/6) = 1/2.
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