Probability

Q.

In his wardrobe, Vignesh has three trousers. One of them is white, the second is blue, and the third is brown. In his wardrobe, he also has four shirts. One of them is white and the other 3 are black. He opens his wardrobe in the dark and picks out one shirt and one trouser without examining the colour. What is the probability that neither the shirt nor the trouser is white?

1. $\frac{2}{3}$

2. $\frac{2}{3}$

3. None of these

4. $\frac{1}{3}$

5. $\frac{1}{2}$

Q. What is the probability that a two digit number selected at random will be a multiple of '3' and not a multiple of '5'?

1. 
2. 
3. 
4. 

Q. Two dice are thrown simultaneously. The probability of getting an even number on both the dice is?

1. 
2. 
3. 
4. 

Q.

Arjith and Karan sit in a ring arrangement with 10 persons. What is the probability that Arjith and Karan will sit together?

1. none

2. 2/11

3. 3/11

4. 7/11

5. 5/9

Q.

How do you find the probability of three events $?$

Q.

The probability that a bullet fired from a point will miss the target is $\frac{3}{4}$. Three such bullets are fired one after the other from that very point. What is the probability that the target will be hit atleast once in three attempts?

1. None of these

2. 

3. 

4. 

5. 

Q.

Three numbers are chosen at random without replacement from $\left\{1,2,...8\right\}$. The probability that their minimum is $3$, given that their maximum is $6$, is

1. $\frac{3}{8}$

2. $\frac{1}{5}$

3. $\frac{1}{2}$

4. $\frac{1}{3}$

Q.

Two decks of cards are there. Each deck contains $20$ cards, with numbers from $1$ to $20$written on them. A card is drawn of random from each deck, getting the numbers $x$ and $y$ what is the probability that $\log x+\log y$ is a positive integer. Logs are taken to the base $10$.

Q.

A gun can fire four shots at a time. If the probabilities of the first, second, third and the last shot hitting the enemy are 0.7, 0.6, 0.5 and 0.4, what is the probability that four shots aimed at an enemy will hit the target?

1. 0.036

2. 0.225

3. 0.964

4. None of these

5. 0.775

Q.

If four vertices of a regular octagon are chosen at random then the probability that the quadrilateral formed by them is a rectangle is

1. $\frac{1}{8}$

2. $\frac{2}{21}$

3. $\frac{1}{32}$

4. $\frac{1}{35}$

Q.

There are 2 bags, which has a total of 50 red balls and 50 blue balls. Each bag has an equal probability of being picked. What is the maximum probability of drawing a red ball, if there are no restrictions on the number of balls that can be put into a bag?

1. 

2. 

3. None of these

4. 

5. 

Q.

Five boys and three girls are seated at random in a row. Find the probability that no boys sits between two girls.

Q.

Guess me:

Make as many $3$-digit numbers as possible whose sum of the digits is $24$ (digits may be repeated).

Q.

Four fair dice are thrown independently $27$ times.

Then the expected number of times, at least two dice show up as a three or a five, is

Q.

A box contains 9 red toys, 9 green toys and 7 blue toys. Each ball is of a different size. The probability that the red ball being selected is the smallest red toy is:

1. $\frac{1}{9}$

2. $\frac{1}{25}$

3. None of these

4. $\frac{8}{9}$

Q.

Probability of getting a prime number when a die is rolled is ‘x’. 4x = ______________.

Q. If a dice is thrown twice, then find the probability of getting $1$ in the first throw only.

1. $\frac{11}{36}$
2. $\frac{7}{36}$
3. $\frac{5}{36}$
4. None of these

Q.

3 cards are drawn from a pack of 52 cards. What is the probability that one is ace, one is queen and one is jack?

1. None of these

2. 

3. 

4. 

Q. A person has to move from A to B. He can only move upwards or towards the right. Find the probability that he passes through C?

1. 1/2
2. 10/21
3. 13/24
4. 1/3
5. 13/34

Q.

Eleven bags of wheat flour, each marked $5$ kg, actually contained the following weights of flour (in kg) $4.975.055.085.035.005.065.084.985.045.075.00$ Find the probability that any of these bags chosen at random contains more than$5$ kg of flour.

Q.

When 8 fair coins are tossed simultaneously, in how many of the outcomes will at most three of the coins turn up as heads?

1. 89

2. 91

3. 79

4. 93

5. 84

Q.

Four different objects A, B, C, D are distributed at random in four places marked A, B, C, D. What is the probability that none of the objects occupy the place corresponding to its alphabet?

1. 1/2

2. 1/3

3. 1/5

4. 1/4

5. None of these

Q. How many three digit numbers have a digital root of 8 with an order 1?

1. 45
2. 36
3. 28
4. 21

Q.

In a lottery, there are 9 prizes and 25 blanks. What is the probability of getting a prize when a lottery is drawn at random?

1. none

2. 1/5

3. 2/5

4. 2/7

5. 9/34

Q.

Karan can take a maximum of four shots at an enemy moving away from him. The probability of hitting the enemy at the first, second, third and fourth shots are 0.3, 0.4, 0.2 and 0.1 respectively. What is the probability that the enemy is hit when all the four shots are fired?

1. 0.6976

2. 0.6864

3. 0.3024

4. None of these

Q. Three different dice are rolled simultaneously three times. The probability that all of them show different numbers only two times, is equal to

1. $100/729$
2. $2/3$
3. $100/243$
4. $175/324$

Q.

Four different objects A, B, C, D are distributed at random in four places marked A, B, C, D. What is the probability that none of the objects occupy the place corresponding to its alphabet?

1. None of these

2. 

3. 

4. 

Q. A person has to move from A to B. He can only move upwards or towards the right. Find the probability that he passes through C?

1. 1/2
2. 13/24
3. 1/3
4. 13/34
5. 10/21

Q.

Arjit and Karan play a game where each one is asked to select a number from 1 to 5. If the two numbers match, both of them win a prize. The probability that they will not win a prize in a single trial is:

1. None of these

2. 

3. 

4. 

Q. Parul and Vijay throw 3 dice in a single throw. It is known that Parul throws a total of 16. Find Vijay’s probability of getting a higher value.

1. 
2. 
3. 
4.