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There is five pink and four green balls in a bucket. if two balls select at random from bucket, find probability of at least one balls are green colour?

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Important Questions on Counting Principles

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Two dices are rolled. If both dices have six faces numbered 1, 2, 3, 5, 7 and 11, then the probability that the sum of the numbers on the top faces is less than or equal to 8 is:
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In a college, 15th of the girls and 18th of the boys took part in a social camp. The total number of students in the college took part in the camp is:

HARD
The probability that a randomly chosen 5- digit number is made from exactly two digits is :
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The numbers a and b are choosen randomly from the set 1,2,3,4,5,6 with replacement such that a and b are prime to each other. Then the probability that is
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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.
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If a is an integer lying in -11,14, then the probability that the graph o y=x2+2a+6x+a+62 is strictly above the x-axis is
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Two letters are chosen from the letters of the word 'EQUATIONS'. The probability that one is vowel and the other is consonant is
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Which of the following cannot be the probability of an event?
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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?
MEDIUM
Let a and b be 2 consecutive integers selected from the first 20 natural numbers. The probability that a2+b2+a2b2 is an odd positive integer is
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Two persons A and B throw a die alternatively till one of them gets a three and wins the game. Find their respective probabilities of winning.
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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?
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There are 6 defective items in a sample of 20 items. One item is drawn at random. The probability that it is a non-defective item is:

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Two numbers x and y are chosen at random from the set {x:0x10,x is an integer). The probability for x-y=5
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In a given village there are only three sizes of families: families with 2 members, familes with 4 members and families with 6 members. The proportion of families with 2,4 and 6 members are roughly equal. A poll is conducted in this village wherein a person is chosen at random and asked about his/her family size. The average family size computed by sampling 1000 such persons from the village would be closest to
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A die is thrown three times and the sum of the three numbers thrown is 15, then the probability that the first throw was a four is
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Six persons A, B, C, X, Y & Z go for an interview. What is the probability of selection of A and Y in the interview?

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?
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?