Tag: some more terms in probability

Questions Related to some more terms in probability

An urn contains 2 red, 3 green and 2 blue balls. If 2 balls are drawn at random, find the probability that no ball is blue.

  1. $\dfrac57$

  2. $\dfrac{10}{21}$

  3. $\dfrac27$

  4. $\dfrac{11}{21}$


Correct Option: B

If the chance that a vessel arrives safely at a port is $\dfrac 9{10}$ then what is the chance that out of $5$ vessels expected at least $4$ will arrive safely?

  1. $\dfrac {14 \times 9^4}{10^5}$

  2. $\dfrac {15 \times 9^5}{10^4}$

  3. $\dfrac {14 \times 9^3}{10^4}$

  4. $\dfrac {14 \times 9^6}{10^5}$


Correct Option: A

A box contains nine bulbs out of which $4$ are defective. If four bulbs are chosen at random, find the probability that all the four bulbs are defective.

  1. $\dfrac{62}{63}$

  2. $\dfrac{125}{126}$

  3. $\dfrac{1}{63}$

  4. $\dfrac{1}{126}$


Correct Option: D

A pot has $2$ white, $6$ black, $4$ grey and $8$ green balls. If one ball is picked randomly from the pot, what is the probability of it being black or green?

  1. $\dfrac34$

  2. $\dfrac1{10}$

  3. $\dfrac43$

  4. $\dfrac7{10}$


Correct Option: D

$10$ books are placed at random in a shelf. The probability that a pair of books will always be together is 

  1. $\dfrac1{5}$

  2. $\dfrac9{10}$

  3. $\dfrac1{10}$

  4. $\dfrac3{10}$


Correct Option: A

A basket contains $6$ blue, $2$ red, $4$ green and yellow balls. If three balls are picked up at random, what is the probability that none is yellow ?

  1. $\dfrac{3}{455}$

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

  3. $\dfrac{4}{5}$

  4. $\dfrac{44}{91}$


Correct Option: D

Successive trials in binomial distribution are

  1. Dependent

  2. Independent

  3. Equally Likely

  4. Mutually exclusive


Correct Option: B

The probability that A speaks truth is $\dfrac35$ and that of B speaking truth is $\dfrac47$. What is the probability that they agree in stating the same fact?

  1. $\dfrac {18}{35}$

  2. $\dfrac {12}{35}$

  3. $\dfrac {17}{35}$

  4. $\dfrac {19}{35}$


Correct Option: A

If the occurrence of one event means that another cannot happen, then the events are

  1. Bayesian

  2. Empirical

  3. Independent

  4. Mutually Exclusive


Correct Option: D

The probability of success of three students X,Y and Z in the one examination are $\dfrac15, \dfrac14$ and $\dfrac13$ respectively. Find the probability of success of at least two.

  1. $\dfrac16$

  2. $\dfrac25$

  3. $\dfrac34$

  4. $\dfrac35$


Correct Option: A