31. A die is tossed twice. Getting a number greater than 4 is considered a success. Then the variance of the probability distribution of the number of successes is :
(a) 2/9 (b) 4/9 (c) 1/27 (d) none of these
Answer
Answer : (b)
Explanation
Explanation : No answer description available for this question. Let us discuss.
Probability » Exercise - 137. In order to get atleast once a head with probability ≥0.9, the number of times a coin needs to be tossed, is : (a) 3 (b) 4 (c) 5 (d) none of these
Probability » Exercise - 113. If A & B are any two events, then the probability that exactly one of them occur is : (a) P (A) + P (B) - P (A ∩B) (b) P (A) + P (B) - 2 P (A ∩B) (c) P (A) + P (B) - P (A ∪B) (d) P (A) + P (B) - 2 P (A ∪B)
Probability » Exercise - 14. The probability of obtaining an even prime number on each die, when a pair of dice is rolled is : (a) 0 (b) 1/3 (c) 1/12 (d) 1/36
Probability » Exercise - 15. 6 coins are tossed simultaneously . The probability of getting atleast 6 heads is : (a) 57/64 (b) 229/256 (c) 7/64 (d) 37/256
Probability » Exercise - 13. A die is tossed thrice. Find the probability of getting an odd number at least once ? (a) 7/5 (b) 6/5 (c) 7/8 (d) 2/8