24ans 1 is (n-2n-1)2
[2]
In a town of population of n,a person sends 2 letters to 2 separate persons,each of whom is asked to repeat the procedure.Thus for each letter recieved,2 letters are sent to 2 separate persons chosen at random,
Let P1,P2,...,Pn be n persons of town.It is given that the person who starts the chain later sends letter to 2 separate persons,each of whom is asked to repeat the procedure
Q1 Find value of P(A2) i.e probablity that P1 dies not recieve a letter at 2nd stage
Q2 Find value of P(A3/A2) i.e probablity that P1 does not recive letter at 3rd stage
Q3 Find value of P(Am/A2 A3 ...Am-1) i.e probablity that P1 does not reciev letter at mth stage
Q4Find probablity that in first m stages,the person who started the chain letters will not recieve the letter
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7 Answers
62see I think you are talking about P(A2) is the probability of recieveing a letter at the 2nd stage!
If he sends the first letter... Probab that he receives the 2nd is (1/n){1 - (2/n)2}
If someone else sends the first letter...
Probability that he recieves the 1st letter is (1-1/n)(2/n)
Probability that he recieves the 2nd letter given that he recieves the 1st letter is (1-1/n)(2/n) {2/n}
Probability that he does not receive the 1st letter is (1-1/n)(1-2/n)
Probability that he recieves the 2nd letter given that he does not receive the 1st letter is (1-1/n)(1-2/n) {1-(1-2/n)2}
I hope this time it is correct?
24its confusing explaiantion.................
cna u expalin a bit more. ???
31) it is (n-2/n-1)2
2)(n-2/n-1)4 and P(P2 doesnt receives letter at the third stage)=(n-2/n-1)8
3)from the above three relations we can conclude tha
P(Am/A2A3.....Am-1)=(n-2/n-1)2m-1
4) so for m stages requird probability=P(A2).(P3/A2∩A1).......P(Am/A2A3.....Am-1)
24Explain all the above answers....
and
Q5 Find probablity that P3 will rite to P1