Probability that "a" speaks truth is 4/5. A coin is tossed. A reports that a head appears. Find out the probability that actually there was head?

Asked by Last Modified  

7 Answers

Follow 2
Answer

Please enter your answer

Maths and Physics teaching For XI, XII, IIT Jee Level , Quant and DI for CAT/GMATE/GRE aspirents

1/10
Comments

4/5 by Bayes theorm
Comments

Tutor

E = event that 'A' reports it is head. E1 = The outcome is head. E2 = outcome is tail. Required. P(E1/E) = P(E/E1) * P(E1)/ P(E) Cases in which 'A' reports heads case 1 when it is head and he is saying the truth = 1/2 * 4/5 case 2 when it is a tail and he is lying. = 1/2 *1/5. Also...
read more
E = event that 'A' reports it is head. E1 = The outcome is head. E2 = outcome is tail. Required. P(E1/E) = P(E/E1) * P(E1)/ P(E) Cases in which 'A' reports heads case 1 when it is head and he is saying the truth = 1/2 * 4/5 case 2 when it is a tail and he is lying. = 1/2 *1/5. Also P(E/E1) = 4/5 (Since, it just denotes the probability of 'A' telling the truth.) So, P(E1/E) = (4/5) * (1/2)/ [{(4/5) * (1/2)}+{(1/5) * (1/2)}] = 4/5 read less
Comments

Maths Teacher

Let E1 be the event A speaks ruth and E2 A does not. A is the event a headappears By Baye's theorem P(E1/A ) = 4/10 /5/10= 4/5
Comments

Mathematics

The correct answer is 4/5
Comments

Let E1 be the event A speaks ruth and E2 A does not. A is the event a headappears By Baye's theorem P(E1/A ) = 4/10 /5/10= 4/5
Comments

Trainer

The probability that there was a head= A speaks truth x probability of falling head= (4/5)x(1/2)= 2/5 ( provided the coin is tossed one time only)
Comments

View 5 more Answers

Related Questions

Discuss the salient features of viruses.
(a) They are smaller than bacteria. (b) They can be filterable. (c) May cause infection and diseases like small pox, flu etc. (d) Able to reproduce in host cells. (e) Use enzymes and metabolic machinery...
Profile Photo
Jitendra
0 0
View Comments6
Guys Hi! I hope your preparation is going well for pre-board exam. Please post any query in math, if you have!
If you are getting ready for the exam then few things are seems very important please go through it without fail: these are from NCERT book .. Exercise 5.1 (11, 13, 15, 19, 20) Exercise 5.2 (example...
Profile Photo
Nilaish
1 0
View Comments6
The magnitude of an electric field does not depend upon __________. (The distance from the charged particle, nature of the charges causing the field, the magnitude of the charges causing the field)
Nature of charge causing the electric field because E = Kq/r^2 here K is constant value is 9 * 10^9 Nm^2/coul^2 but direction of Electric field is away from +q and towards the -q
Profile Photo
Narendra Kumar

Now ask question in any of the 1000+ Categories, and get Answers from Tutors and Trainers on UrbanPro.com

Ask a Question

Related Lessons

Utility and its features
What is Utility and what are its features?
Profile Photo

ELECTROCHEMISTRY
(a) The process of chemical decomposition of an electrolyte on the passing of electric current through its aqueous solution or in its molten state is known as electrolysis.(b) It involves oxidation...
Profile Photo

Square Of a Number Ending In 5
Let's say we want to get the square of 35 i,e 35 x 35, Take the first no ie 3,take the next number i,e 4, Multiply 3 and 4 ie 3 x 4 = 12, Place 25 after 12, So, the answer is 1225, Lets try some more, 75...
Profile Photo

Permutations And Combinations
Q: There are 9 objects and 9 boxes. Out of nine objects, 5 can not fit in three small boxes. How many arrangements can vere made such that each object can put in one box only? Ans : As 5 objects can not...
Profile Photo

Guarantee Of Profits To A Partner.
Guarantee is an assurance given to the partner of the firm that at least a fixed amount shall be given to him/her irrespective of his/her actual share in profits of the firm. If actual share in profits...
Profile Photo

Recommended Articles

Swati is a renowned Hindi tutor with 7 years of experience in teaching. She conducts classes for various students ranging from class 6- class 12 and also BA students. Having pursued her education at Madras University where she did her Masters in Hindi, Swati knows her way around students. She believes that each student...

Read full article >

Urmila is a passionate teacher with over 8 years of experience in teaching. She is currently pursuing her Ph. D. She provides classes for Class 11, Class 12, MBBS and Medical tuition.  Urmila began her career in teaching long before she became a teacher. She used to provide classes for foreign national students in her college...

Read full article >

Raghunandan is a passionate teacher with a decade of teaching experience. Being a skilled trainer with extensive knowledge, he provides high-quality BTech, Class 10 and Class 12 tuition classes. His methods of teaching with real-time examples makes difficult topics simple to understand. He explains every concept in-detail...

Read full article >

Mohammad Wazid is a certified professional tutor for class 11 students. He has 6 years of teaching experience which he couples with an energetic attitude and a vision of making any subject easy for the students. Over the years he has developed skills with a capability of understanding the requirements of the students. This...

Read full article >

Looking for Class 12 Tuition ?

Learn from the Best Tutors on UrbanPro

Are you a Tutor or Training Institute?

Join UrbanPro Today to find students near you