A random variable X has the following probability distribution:
then which of the following are TRUE? (A) $k=0.1$ (B) $P(X < 1) = 0.4$ (C) $P(X < 2) = 0.7$ (D) $P(0 < x < 3) = 0.5$ Choose the correct answer from the options given below. |
(A), (B) and (D) only (A), (B) and (C) only (A), (B), (C) and (D) (B), (C) and (D) only |
(A), (B), (C) and (D) |
The correct answer is Option (3) → (A), (B), (C) and (D) ** Given probabilities: $0.1,\;0.2,\;k,\;0.3,\;2k,\;0.1$ Sum must be 1: $0.1+0.2+k+0.3+2k+0.1 = 1$ $0.7 + 3k = 1$ $3k = 0.3$ $k = 0.1$ ✔ Now check statements: (A) $k = 0.1$ ✔ (B) $P(X < 1) = P(-2)+P(-1)+P(0)$ $= 0.1 + 0.2 + 0.1 = 0.4$ ✔ (C) $P(X < 2) = P(-2) + P(-1) + P(0) + P(1)$ $= 0.1 + 0.2 + 0.1 + 0.3 = 0.7$ ✔ (D) $P(0 < X < 3) = P(1) + P(2)$ $= 0.3 + 0.2 = 0.5$ ✔ Correct statements: (A), (B), (C), (D) |