Recent questions and answers in Probability

Let X denote the sum of the numbers obtained when two fair dice are rolled. Find the variance and standard deviation of X.

answered Feb 18, 2020 by surafelalemgirma91

2 answers

P(A speaks truth is) = 4/5 . A coin is tossed. 'A' reports that a head appears. The probability that actually there was a head is.

answered Jul 13, 2019 by fad.vhora

1 answer

Given P(A) = 0.3, P(B) = 0.2, Find P(B/A) if A and B are mutually exclusive events.

answered Jul 1, 2019 by abhav31

5 answers

Three persons,A,B and C,fire at a target in turn,starting with A.Thier probability of hitting the target are 0.4,0.3 and 0.2 respectively.The probability of two hits is

answered Mar 12, 2019 by meena.clay6

1 answer

The mean and variance of a binomial distribution are $ 4 \;and\;\frac{4}{3}.\;Find\;P(X\geq1).$

answered Feb 26, 2018 by Sumitchn007

1 answer

In a game, a man wins a rupee for a six and loses a rupee for any other number when a fair die is thrown. The man decided to throw a die thrice but to quit as and when he gets a six. Find the expected value of the amount he wins / loses.

answered Jan 28, 2018 by sristijain30

2 answers

A letter is known to have come either from TATA NAGAR or from CALCUTTA.On the envelope,just two consecutive letter TA are visible.What is the probability that the letter came from TATA NAGAR.

answered Jul 30, 2017 by Prathapchaithanya99

2 answers

Suppose a girl throws a die. If she throws a 5 or 6, she tosses a coin 3 times and notes the number of heads. If she gets 1, 2, 3 or 4, she tosses a coin once and notes whether a head or tail is obtained. If she obtained exactly one head, what is the probability that she threw 1, 2, 3 or 4 with a die?

answered Dec 27, 2016 by priyanka.c

1 answer

A die is thrown 10 times. If getting a prime number is considered a success, find the probability of getting not more than 8 successes.

answered Dec 20, 2016 by priyanka.c

1 answer

If the letters of the word 'ASSASSINATION' are arranged at random in a row, find the probability that
(a) four S's come consecutively in the word
(b) All A's not coming together
(c) two I's and two N's come together.

answered Dec 19, 2016 by priyanka.c

1 answer

From a group of 7 men and 4 ladies, a committee o 6 persons is formed. What is the probability that the committee will consist exactly of 2 ladies ?

answered Dec 10, 2016 by priyanka.c

1 answer

In a game, a man wins a rupee for a six and loses a rupee for any other number when a fair die is thrown. The man decided to throw a die thrice but to quit as and when he gets a six. Find the expected value of the amount he wins / loses.

answered Dec 8, 2016 by priyanka.c

1 answer

A coin is tossed 6 times. What Is the probability that tail appears an odd no of times ?

answered Nov 30, 2016 by priyanka.c

1 answer

Event A and B are such that $P(A) = \frac{1}{2}, P(B) = \frac{7}{12} $, P (not A or not B) =$ \frac{1}{4}$. State whether A and B are independent.

answered Nov 23, 2016 by priyanka.c

1 answer

Two eggs are drawn successively with replacement from a lot containing 10% defective eggs. Find the probability that there is at least one defective egg.

answered Nov 19, 2016 by priyanka.c

1 answer

Two cards are drawn without replacement from a well shuffled pack of 52 cards. Find the probability that one is spade and other is a queen of red colour.

answered Nov 18, 2016 by priyanka.c

1 answer

A die which is marked with 1, 2, 3 in red and 4, 5, 6 in green is tossed. Let A be the event 'number is even' and B be the event 'number is red' and Are A and B independent?

answered Nov 17, 2016 by priyanka.c

1 answer

Six dice are thrown 729 times. How many times do you expect atleast three dice to show 5 or 6.

answered Mar 23, 2016 by vijayalakshmi.r

1 answer

Obtain the probability distribution of number of sixes in two tosses of a dice. Also find mean/ variance.

answered Aug 8, 2015 by csyogendra21

1 answer

State Biot Savart law. Use it to obtain the intensity of magnetic field at a point due to a long straight current carrying wire.

asked Feb 10, 2015 by meena.p

0 answers

Draw the logic circuit of a $NAND$ gate and wite its truth table.

asked Jan 28, 2015 by meena.p

0 answers

Five cards are drawn successively with replacement from a well-shuffled deck of 52 cards. What is the probability that (i) all the five cards are spades? (ii) only 3 cards are spades? (iii) none is a spade?

answered Mar 20, 2014 by balaji.thirumalai

1 answer

What is the difference between Bayes theorem and Total Probability theorem?

answered Feb 12, 2014 by rvidyagovindarajan_1

1 answer

A bag contains 4 balls. Two balls are drawn at random and are found to be white. What is the probability that the bag has 3 white balls.

answered Jan 31, 2014 by rvidyagovindarajan_1

1 answer

Suppose you roll 5 dice and sum up the highest 3 numbers. What is the probability that the sum is 18?

answered Jan 30, 2014 by balaji

1 answer

Suppose that 5% of men and 0.25% of women have grey hair. A grey haired person is selected at random. What is the probability of this person being male? Assume that there are equal number of males and females.

answered Jan 30, 2014 by balaji

1 answer

A die is thrown120 times and getting 1 or 5 is considered success. Find the mean,varianceof numberofsuccesses.

answered Jan 16, 2014 by rvidyagovindarajan_1

1 answer