Quants Questions: Probability Set 2

Hello Aspirants. Welcome to Online Maths in AffairsCloud.com. Here we are creating question sample in Probability, which is common for all the competitive exams. We have included Some questions that are repeatedly asked in exams !!

1. Out of 6 green ball, 4 blue ball, in how many ways we select one or more balls ?
   A)42
   B)34
   C)31
   D)22
   E)None of these
   
   Answer

   B)34
   Explanation :7*5 = 35
   35 – 1 = 34
   
   
   
2. P and Q throw a dice.Find the probability that P’s throw is not greater than Q’s through
   A)7/5
   B)12/7
   C)7/12
   D)7/11
   E)None of these
   
   Answer

   C)7/12
   Explanation :
   A         B
   1          1 2 3 4 5 6
   2          2 3 4 5 6
   3          3 4 5 6
   4          4 5 6
   5          56
   6          6
   n(E) = 21
   n(S) = 36
   P = 21/36 = 7/12
   
   
   
3. An unbiased die is tossed. Find the probability of getting of getting a multiple of 2.
   A)2
   B)3
   C)1/2
   D)1/3
   E)None of these
   
   Answer

   C)1/2
   Explanation :
   2, 4,6   multiple of 3
   n(E) = 3
   n(S) = 6
   p = 3/6 = 1/2
   
   
   
4. A bag contains 3 green, 5 black and 4 brown balls. 3 balls are drawn randomly. What is the probability that balls drawn contain different colours of balls?
   A)11/7
   B)2/11
   C)11/3
   D)3/11
   E)None of these
   
   Answer

   D) 3/11
   Explanation :
   Toatal numbers of balls = 12
   n(S) = 12C₃ = 220
   n(E) = 3C1 ×5C1×4C1  = 4 × 3 × 5 = 60
   P = 60/220 = 3/11
   
   
   
5. A bag contain 2 red, 3 blue and 6 green plates. One plate is taken up randomly. What is the probability that it is neither red nor green ?
   A)3/11
   B)2/11
   C)7/11
   D)11/3
   E)None of these
   
   Answer

   A)3/11
   Explanation :
   n(S) = 2+3+6 = 11
   n(E) = 3
   P = 3/11
   
   
   
6. In a college 10% of the students speaking English, 70%  speaking Hindi and 10% speaking both.If a students is selected at random, what is the probability of the students who speak English or Hindi ?
   A)9/5
   B)10/7
   C)7/10
   D)5/7
   E)None of these
   
   Answer

   C)7/10
   Explanation :
   P(a) = 10/100 = 1/10
   P(b) = 70/100 = 7/10
   P(both) = 10/100 = 1/10
   P(a U b) = (1+7-1)/10 = 7/10
   
   
   
7. A bag contains 4 pink dresses, 5 red shirts and 3 yellow shirts. 3 dresses are drawn randomly. What is the probability that exactly one of them is pink ?
   A)65/104
   B)56/110
   C)25/110
   D)36/28
   E)None of these
   
   Answer

   B)56/110
   Explanation :
   Total no of shirts = 12C3 = 220
   4c1 × 8c2 = 112
   P = 112/220 = 56/110
   
   
   
8. A bag contain 2 red, 3 blue and 6 green plates. One plate is taken up randomly. What is the probability that it is either red or green ?
   A)8/11
   B)11/8
   C)10/7
   D)3/11
   E)None of these
   
   Answer

   A)8/11
   Explanation :
   Total = 2+3+6 = 11
   either red nor green = 2+6 = 8
   p = 8/11
   
   
   
9. In a box 4 blue pens, 3 red pens and 5 black pens. If 2 pens taken from the box, What is the probability that both of them are same colour pens ?
   A)66/19
   B)15/28
   C)18/35
   D)19/66
   E)None of these
   
   Answer

   D)19/66
   Explanation :
   ⁴c₂ + ³c₂ + ⁵c₂  = 6+3+10  = 19
   ¹²c₂ = 66
   P = 19/66
   
   
   
10. From a pack of 52 cards, 3 cards are drawn together at random, What is the probability of both the cards are king ?
    A)1/5225
    B)1/5525
    C)5525
    D)1/525
    E)None of these
    
    Answer

    B)1/5525
    Explanation :
    n(S) = ⁵²C₃ =  132600/6 = 22100
    n(E) = ⁴C₃ = 24/6 = 4
    p = 4/22100 = 1/5525