logo

CuriousTab

CuriousTab

Discussion


Home Aptitude Probability Comments

  • Question
  • Murari has 9 pair of dark blue socks and 9 pair of black socks. He keeps them all in the same bag. If he picks out three socks at random What is the probability that he will get a matching pair?


  • Options
  • A. 9c3 x 9c1/ 18c3
  • B. 2 x 9c3 x 9c1/ 18c3
  • C. 1
  • D. 4/7

  • Correct Answer


  • Explanation

    Since, there are only two types of socks in the bag. so, if murari pick up 3 socks then certainly two of them are of same type. Thus this is a certain event.
    Hence required probability = 1


  • Probability problems


    Search Results


    • 1. 
      In a ward-robe, Nitish has 3 trousers. One of them is black, second is blue and third brown. In this ward-robe, he has 4 shirts also. One of them is black and the other 3 are white. He opens his ward-robe in the dark and picks out one shirt-trouser pair without examining the colour. What is the likelihood that neither the shirts nor the trousers are black?

    • Options
    • A. 1/12
    • B. 1/6
    • C. 1/4
    • D. 1/2
    • Discuss
    • 2. 
      A bag contains 3 red, 4 white and 7 black balls. The probability of drawing a red or a black ball, is

    • Options
    • A. 4/7
    • B. 1/7
    • C. 5/7
    • D. 3/7
    • Discuss
    • 3. 
      A box contains 24 marbles, some are green and other are blue. If a marble is drawn at random from the box, the porbability that it is green is 2/3. The number of blue balls in the box is

    • Options
    • A. 13
    • B. 12
    • C. 16
    • D. 8
    • Discuss
    • 4. 
      A and B are two events such that P(A) = 0.3 and P ( A?B) = 0.8. If A and B are independent, then P (B) is

    • Options
    • A. 2/3
    • B. 3/8
    • C. 2/7
    • D. 4/7
    • Discuss
    • 5. 
      Five coins are tossed at a time. Then, the probability of obtaining at least one tail is

    • Options
    • A. 31/32
    • B. 1/32
    • C. 1/5
    • D. 5/32
    • Discuss
    • 6. 
      An anti-aircraft gun can take a maximum of four shots at an enemy plane moving away from it ,The probability of hitting the plane at the first, second, third and fourth shots are 0.4, 0.3, 0.2, and 0.1 respectively. What is the probability that the plane is hit when all the four shots are fired?

    • Options
    • A. 0.4379
    • B. 0.6872
    • C. 0.6976
    • D. 0.3507
    • Discuss
    • 7. 
      Four boys and three girl stand in queue for an interview. The probability that they stand in alternate position is

    • Options
    • A. 1/34
    • B. 1/35
    • C. 1/17
    • D. 1/68
    • Discuss
    • 8. 
      An elevator starts with 5 passengers and stops at 8 different floors if the house. Find out the probability of all the 5 passengers alighting at different floors.

    • Options
    • A. 101/512
    • B. 105/512
    • C. 107/512
    • D. 109/512
    • Discuss
    • 9. 
      If one cap is picked at random, what is the probability that it is either blue or yellow?

    • Options
    • A. 2/9
    • B. 1/4
    • C. 3/8
    • D. 6/11
    • Discuss
    • 10. 
      If three marbles are picked at random, what is the probability that either all are green or all are red?

    • Options
    • A. 7/44
    • B. 7/12
    • C. 5/12
    • D. 1/44
    • Discuss


    Comments

    There are no comments.

Enter a new Comment