HARD
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In a lottery, there are 10 prize and 25 blanks. A lottery is drawn at random. What is the probability of getting a prize?

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Important Questions on Probability

MEDIUM
Three players A, B  and C play a game. The probability that A,B and C will finish the game are respectively 12,13 and 14 . The probability that the game is finished is.
HARD

Consider the following events:

E1 : Six fair dice are rolled and at least one die shows six
E2 : Twelve fair dice are rolled and at least two dice show six
Let p1 be the probability of E1 and p2 be the probability of E2. Which of the following is true ?

HARD
For three events, A, B and C, P(Exactly one of A or B occurs)

=P(Exactly one of B or C occurs)

=P(Exactly one of C or A occurs) =14 and P(All the three events occur simultaneously) =116.

Then the probability that at least one of the events occurs, is:
HARD
An unbiased coin is tossed eight times. The probability of obtaining at least one head and at least one tail is:
EASY
What is the probability that a number selected from numbers 1,2,3,_______ 30, is a prime number, when each of the given numbers is equally likely to be selected?
HARD
Three persons P, Q and R independently try to hit a target. If the probabilities of their hitting the target are 34,12 and 58 respectively, then the probability that the target is hit by P or Q but not by R is:
EASY
If A and B are events with PAB=34,P A=23 and PAB=14 then PB is
MEDIUM
In a box, there are 20 cards, out of which 10 are labelled as A and the remaining 10 are labelled as B . Cards are drawn at random, one after the other and with replacement, till a second A card is obtained. The probability that the second A card appears before the third B card is:
MEDIUM
There are 6 red balls and 4 yellow balls in a bag. Two balls are simultaneously drawn at random. What is the probability that both the balls are of same colour?
MEDIUM
If the probability of hitting a target by a shooter, in any shot is 13, then the minimum number of independent shots at the target required by him so that the probability of hitting the target at least once is greater than 56, is:
HARD
If Aand B are two events such that PAB=PAB, then the incorrect statement amongst the following statements is :
EASY
There are 3 red balls, 4 blue balls and 5 white balls. 2 balls are chosen randomly. Find the probability that one is red and the other is white.
HARD
Minimum number of times a fair coin must be tossed so that the probability of getting at least one head is more than 99%  is:
HARD
Four persons independently solve a certain problem correctly with probabilities 12,34,14,18. Then the probability that the problem is solved correctly by at least one of them is
EASY
If three dices are thrown then the probability that the sum of the numbers on their uppermost faces to be atleast 5 is
MEDIUM
The probabilities of three events A,B and C are given PA=0.6, PB=0.4 and PC=0.5. If PAB=0.8, PAC=0.3, PABC=0.2, PBC=β and PABC=α, where 0.85α0.95, then β lies in the interval :
EASY
Let A and B be two events such that the probability that exactly one of them occurs is 25 and the probability that A or B occurs is 12, then the probability of both of them occur together is
HARD
In a class of 60 students, 40 opted for NCC, 30 opted for NSS and 20 opted for both NCC and NSS. If one of these students is selected at random, then the probability that the student selected has opted neither for NCC nor for NSS is :
EASY
A bag contains 6 black and 8 white balls. One ball is drawn at random. What is the probability that the ball drawn is white?
MEDIUM
A bag contains 3 red balls, 5 yellow balls and 7 pink balls. If one ball is drawn at random from the bag, what is the probability that it is either pink or red?