Probability

Study Material (PDF)
Self Assesment
Study Material (PDF)
Self Assesment

Click on each question to see answer & solution.

Question No: #31

If odds against an event is `2:3`, then the probability of that event is --
(a) `2/5`, (b) `3/5`, (c) `2/3`, (d) `1/5`
Ans: (b) `3/5`
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Question No: #32

If the probability of an event is `5/8`, then odds against this event is --
(a) `5:13`, (b) `5:3`, (c) `3:5`, (d) `8:13`
Ans: (c) `3:5`
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Question No: #33

7 white balls and 3 black balls are randomly placed in a row. The probability that no two black balls are placed adjacently is -
(a) `1/2`, (b) `7/15`, (c) `2/15`, (d) `1/3`
Ans: (b) `7/15`
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Question No: #34

If `P(A \cap B) = 5/13`, then the value of `P(A^c \cup B^c)` is --
(i) `4/13`, (ii) `6/13`, (iii) `7/13`, (iv) `8/13`
Ans: iv) `8/13`
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Question No: #35

If `P(A) = 1/4`, `P(B) = 1/2` and `P(A \cup B) = 5/9`, then `P(A | B) = ` ?
Ans: `7/18`
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Question No: #36

If `P(A) = 1/12`, `P(B) = 5/12` & `P(B | A) = 1/15`, then value of `P (A \cup B)` is -
(a) `89/180`, (b) `91/180`, (c) `93/180`, (d) `87/180`
Ans: (a) `89/180`
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Question No: #37

If the two events `A` & `B` are such that `2P(A) = P(B) = 5/13` and `P(A | B) = 2/3`, then find `P(A \cup B)`
Ans: `25/78`
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Question No: #38

If `P(A) = 1/5`, `P(B) = 2/3` & `P(A \cap B) = 4/15`, then verify that `A` & `B` are exhaustive events.
Ans: Not mutually exhaustive
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Question No: #39

If `P(A) = 2/3`, `P(B) = 1/2` and `P(A \ cap B) = 1/6` then find `P(A \cap B^c)`
Ans: `1/2`
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Question No: #40

If `P(A) = 3/7`, `P(B) = 4/7` and `P(A \cap B) = 2/9`, then the value of `P(A | B)` is --
(a) `7/18`, (b) `14/27`, (c) `5/18`, (d) `4/9`
Ans: (a) `7/18`
SEE SOLUTION