Recent questions tagged probability

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Prove for a positive integer valued random variable, $X$ , and for positive integers $a < b$\begin{align*} &P(X \geq b) \leq \left [ \left ( \frac{E(X)}{b} \right ) - P(...
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754
A class of $30$ students occupy a classroom containing $5$ rows of seats, with $8$ seats in each row. If the students seat themselves at random, the probability that sixt...
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Suppose X is a uniform random variable between 0.50 and 1.00. What is the probability that a randomly selected value of X is between 0.55 and 0.60 or between 0.75 and 0.8...
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756
Three person plays a game by tossing a coin, if atleast one of the outcome is different from another end is declared, coins are biased with probability of head is 1/4 wha...
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4 person wearing different hat went to restaurant, they gave there hat to manager, manager has habit of forgetting thing while returning manager gave hat back to each per...
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Six balls are to be randomly chosen from an urn containing 8 red, 10 green, and 12 blue balls.What is the probability at least one red ball, one blue and one green ball i...
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A student has to answer $9$ out of $12$ questions. How many ways if he has to answer at least $4$ out of first $5$ questions?
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From a pack of $52$ cards, all the face cards are removed and four cards are drawn. Then the probability that they are of different suit and different denomination is
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Two players,$A$ and $B$,alternately keep rolling a fare dice.The person to get six first wins the game.Given that player $A$ starts the game,the probability that $A$ wins...
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767
A fair coin is tossed till a head appears for the first time.The probability that the number of required tossed is odd,is$\left(\dfrac{1}{3}\right)$$\left(\dfrac{1}{2}\ri...
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Two integers $m$ and $n$ are chosen at random with replacement from the natural numbers $1,2,.....9$. The probability that $m^2-n^2$ is divisible by $4$ is$\dfrac{41}{81}...
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If a certain normal distribution of $X$, the probability is $0.5$ that $X$ is less than $500$ and $0.0227$ that $X$ is greater than $650$. What is the standard deviation ...
2 votes
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There are 60 persons in a room.We have choosen 10 person at random. What is the probability that exactly 2 person among them have same birthday?