Home
Class 12
MATHS
If bar E and bar F are the complement...

If ` bar E and bar F ` are the complementary events of events `E and F ,` respectively, and if `0 < P(F)<1,` then a.`P(E/F)+P( bar E / F )=1` b. `P(E/F)+P(E/bar F )=1` c. `P( barE /F)+P(E/ bar F )=1` d. `P(E/ barF )+P( bar E / bar F )=1`

A

`P(E//F)+P(overset(" "-)(E )//F)=1`

B

`P(E//F)+P(E //overset(" "-)(F))=1`

C

`P(overset(" "-)(E)//F)+P(E//overset(" "-)(F))=1`

D

`P(E//overset(" "-)(F))+P(overset(" "-)(E)//overset(" "-)(F))=1`

Text Solution

Verified by Experts

The correct Answer is:
A, B

`(a) P(E//F) + P(bar(E)//F) = (P (E nn F))/(P(F)) + (P(bar(E) nn F))/(P(F))`
` = (P(E nn F) + P( bar(E) nn F))/(P(F))`
` = (P(F))/(P(F)) = 1`
Therefore, option (a) is correct.
`(b) P(E//F) + P(E//bar(F)) = (P(E nn F))/(P(F)) + (P(E nn bar(F)))/(P(bar(F)))`
` = (P(E nn F))/(P(F)) + (P(E nn bar(F))/(1-P(F)) ne 1`
Therefore, option (b) is not correct.
`(c) P(bar(E)//F) + P(E// bar(F)) = (P(bar(E) nn F))/(P(F)) + (P(E nn bar(F)))/(P(bar(F)))`
`= (P (bar(E) nn F))/(P(F)) + (P(E nn bar(F)))/(1-P(F)) ne 1`
Therefore, option (c) is not correct.
`(d) P(E//bar(F)) + P(bar(E)//bar(F)) = (P(E nn bar(F)))/(P(bar(F))) + (P(bar(E) nn bar(F)))/(P(bar(F)))`
` = (P(bar(F)))/(P(bar(F))) = 1`
Therefore, option (d) is correct.
Promotional Banner

Similar Questions

Explore conceptually related problems

Prove that if E and F are independent events, then so are the events E and F'.

Let A and B be two events such that p( bar (AuuB))=1/6, p(AnnB)=1/4 and p( bar A)=1/4 , where bar A stands for the complement of the event A. Then the events A and B are (1) mutually exclusive and independent (2) equally likely but not independent (3) independent but not equally likely (4) independent and equally likely

Write of any five pair of events that are complementary.

If E and F are independent events, show that P(EuuF) =1- P(E') P(F') .

In case of a die is getting a 1 complementary to events getting 2, 3, 4, 5, 6? Give reasons for your answer

Let A and B be two events such that P (bar(AuuB))=1/6, P(AnnB)=1/4and P(barA)=1/4,where barA stands for the complement of the event A. Then the events A and B are

If E and F are independent events such that P(E')=0.2 and P(F')=0.5, find P(EnnF)

Let E^c denote the complement of an event E. Let E,F,G be pairwise independent events with P(G) gt 0 and P(E nn F nn G)=0 Then P(E^c nn F^c nn G) equals (A) P(E^c)+P(F^c) (B) P(E^c)-P(F^c) (C) P(E^c)-P(F) (D) P(E)-P(F^c)

In an a.c circuit the e.m.f(e) and the current (i) at any instant are given respectively by :

One card is drawn at random from a well shuffled deck of 52 cards. In which of the following cases are the events E and F independent? i. E: 'the card drawn is a spade' F: 'the card drawn is an ace' ii. E: 'the card drawn is black' F: 'the card drawn is king' ii. E: 'the card drawn is a king or queen' F: 'the card drawn is a queen or jack'.