Quantitative Aptitude - Probability

26. A man alternately tosses a coin and throw:, a dice, beginning with the coin. Then the probability that he will get a head before he gets a 5 or 6 on dice is

  • Option : B
  • Explanation : Probability

    Let A be the event of getting 5 or 6
    P(A) = 1/3 and B be the event of getting 1,2,3,4
    P(B) = 2/3
    In order to get a 'Head' before "5 or 6",  the
    following events have to occur:
    H, TBH, TBTBH, TBTBTBH, ....

     Probability

Cancel reply

Your email address will not be published. Required fields are marked *


Cancel reply

Your email address will not be published. Required fields are marked *


27. Six dice are thrown simultaneously. The probability that all will show different faces is

  • Option : B
  • Explanation : Number of ways different numbers can occur
    on six dice = 6!

    Total number of ways of occurrence = 65
    Required probability,  Probability

Cancel reply

Your email address will not be published. Required fields are marked *


Cancel reply

Your email address will not be published. Required fields are marked *


28. A box A contains 2 white and 4 black balls. Another box B contains 5 white and 7 black balls. A ball is transferred from the box A to the box B, Then a ball is drawn from the box B The probability that it is white is

  • Option : A
  • Explanation : Probability of drawing a white ball from Box B will depend on whether 
    transferred ball is black or white.
    If a black ball is transferred then its probability is 4/6
    There are now 5 white and 8 black balls in the
    box B. Then probability of drawing white ball
    from the Box B = 5/13
    Hence probability of drawing a white ball from
    urn B, if the transferred ball is black

                                              Probability

    Similarly, probability of drawing a white ball
    from urn E, if transferred ball is white

     Probability

Cancel reply

Your email address will not be published. Required fields are marked *


Cancel reply

Your email address will not be published. Required fields are marked *


29. If P (A) = 0, then P (A ∩ B) =?

  • Option : A
  • Explanation : P(A) = 0
    A = φ
    A ∩ B = φ
    P(A ∩ B) = P(φ) = 0
Cancel reply

Your email address will not be published. Required fields are marked *


Cancel reply

Your email address will not be published. Required fields are marked *


30. Which of the following is correct?

Cancel reply

Your email address will not be published. Required fields are marked *


Cancel reply

Your email address will not be published. Required fields are marked *


Related Quiz.
Probability