MEDIUM
JEE Main
IMPORTANT
Earn 100

A six faced die is biased such that 3×P(a prime number)=6×P(a composite number)=2×P1. Let X be a random variable that counts the number of times one gets a perfect square on some throws of this die. If the die is thrown twice, then the mean of X is

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Important Questions on Probability

MEDIUM
JEE Main
IMPORTANT
Out of 60% female and 40% male candidates appearing in an exam, 60% candidates qualify it. The number of females qualifying the exam is twice the number of males qualifying it. A candidate is randomly chosen from the qualified candidates. The probability, that the chosen candidate is a female, is
MEDIUM
JEE Main
IMPORTANT

Let A and B be two events such that PBA=25, PAB=17 and PAB=19. Consider 

S1: PA'B=56,

 S2: PA'B'=118. Then

MEDIUM
JEE Main
IMPORTANT
A bag contains 4 white and 6 black balls. Three balls are drawn at random from the bag. Let X be the number of white balls, among the drawn balls. If σ2 is the variance of X, then 100σ2 is equal to
MEDIUM
JEE Main
IMPORTANT
Let S=1,2,3,,2022. Then the probability, that a randomly chosen number n from the set S such that HCFn,2022=1, is
MEDIUM
JEE Main
IMPORTANT
Bag I contains 3 red, 4 black and 3 white balls and Bag II contains 2 red, 5 black and 2 white balls. One ball is transferred from Bag I to Bag II and then a ball is draw from Bag II. The ball so drawn is found to be black in colour. Then the probability, that the transferred ball is red, is
MEDIUM
JEE Main
IMPORTANT
The sum and product of the mean and variance of a binomial distribution are 82.5 and 1350 respectively. They the number of trials in the binomial distribution is
EASY
JEE Main
IMPORTANT

Let Ω be the sample space and AΩ be an event. Given below are two statements:

S1: If P(A)=0, then A=ϕ

S2: If P(A)=1, then A=Ω

Then

HARD
JEE Main
IMPORTANT
The urns A, B and C contains 4 red, 6 black; 5 red, 5 black and λ red, 4 black balls respectively. One of the urns is selected at random and a ball is drawn. If the ball drawn is red and the probability that it is drawn from urn C is 0.4, then the square of length of the side of largest equilateral triangle, inscribed in the parabola y2=λx with one vertex at vertex of parabola is