MCQ On Class 12 Maths Chapter 13 Probability

1 If the event A and B are independent, then P(A∩B) is equal to

A P(a) + P(b)

B P(a) – P(b)

C P(a). P(b)

D P(a) | P(b)

View Answer

Answer:P(a). P(b)

2 If two events are independent, then

A they must be mutually exclusive

B the sum of their probabilities must be equal to 1

C (a) and (b) both are correct

D None of the above is correct

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Answer:None of the above is correct

3 If A and B are such that events that P(a) > 0 and P(b) ≠ 1, then P (A’|B’) equal

A 1 – P (A|B)

B 1 – P(A’|B)

C

D p(A’) | P(B’)

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Answer:

4 You are given that A and B are two events such that P(b) = 3/5, P(A|B) = 1/2 and P (A∪B) = then P(B|A’) equals

A 1/5

B 3/10

C 1/2

D 3/5

View Answer

Answer:3/5

5 If A and B are two events and A ≠ Φ, B ≠ Φ, then

A P (A|B) = P (a). P (b)

B

C P (A + B). P (B|A) = 1

D P (A|B) = P (a) | P (b)

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Answer:

6 If P(a) = 4/5 and P(A∩B) = 7/10, then P(B/A) is equal

A 1/10

B 1/8

C 7/8

D 17/20

View Answer

Answer:17/20

7 If A, B are two events associated with same random experiment such that P(a) = 0.4, P(b) = 0.8 and P(B/A) = 0.6 then P(A/B) is

A 0.3

B 0.4

C 0.5

D 0.6

View Answer

Answer:0.3

8 Two dice are tossed once. The probability of getting an even number at the first dice ora total of 8 is

A 1/36

B 3/36

C 11/36

D 5/9

View Answer

Answer:5/9

9 If P(b) = 1/5, P(A|B) = 1/2 and P(A∪B) = 4/5 then P (A∪B)’ + P (A’∪B) =

A 1/5

B 4/5

C 1/2

D 3/5

View Answer

Answer:3/5

10 A and B are events such that P(a) = 0.4, P(b) = 0.3 and P(A∪B) = 0.5. Then P(B∩A) equals

A 2/3

B 1/2

C 3/10

D 1/5

View Answer

Answer:1/5

11 If P(A∩B) = 7/10 and P(b) = 17/20, then P(A|B) equals

A 14/17

B 17/20

C 7/8

D 1/8

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Answer:14/17

12 An experiment has 10 equally likely outcomes. Let A and B be two non-empty events of the experiment. A consists 4 outcomes, the number of outcomes that B must have so that A and B are independent is

A 2, 4 or 8

B 36 or 9

C 4 or 8

D 5 or 10

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Answer:5 or 10

13 You are given that A and B are two events such that P(b) = 3/5, P(A|B) = 1/2 and P (A∪B) = 4/5, then P(a) equals

A 3/10

B 1/5

C 1/2

D 3/5

View Answer

Answer:1/2

14 A pair of dice are rolled. The probability of obtaining an even prime number on each dice is

A 1/36

B 1/12

C 1/6

D 0

View Answer

Answer:1/36

15 The probability that A speaks truth is 4/5 while this probability for B is 3/4. The probability that they contradict each others when asked to speak ana fact is

A 7/20

B 1/5

C 3/20

D 4/5

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