Home › JEE Main › Mathematics › Statistics and Probability › A box has 6 balls, 4 are red. Two balls drawn (w…
A box has 6 balls, 4 are red. Two balls drawn (without replacement). P(both red):
A1/15
B1/2
CC(4,2)/C(6,2) = 6/15 = 2/5
D1/3
Answer & Solution
Correct answer: C. C(4,2)/C(6,2) = 6/15 = 2/5
P(both red) = 4C2 / 6C2 = 6/15 = 2/5 = 0.4.
Related questions
For a random variable X, the variance Var(X) equalsIf P(A) = 0.4, P(B|A) = 0.5, then P(A ∩ B) equalsTwo dice are rolled. Let E = "sum is 8" and F = "at least one die shows 4". Then P(E|F) eqE and F are independent events with P(E) = 0.3 and P(F) = 0.5. Then P(E ∪ F) equalsA card is drawn at random from a well-shuffled deck of 52. E = "card is a face card" (KingFor a Binomial distribution B(n, p), the probability of exactly r successes isThe variance of the number of heads in 3 fair-coin tosses isA random variable X counts the number of heads in 3 tosses of a fair coin. The mean E(X) i