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Grade 12Analytical Geometry

Q1. A and B are 2 independent witnesses in a case.The probability that A will speak the truth is t1 and the probability that B will speak the truth is t2.If both A and B agree on a certain statement,what is the probability that the statement is true? Q2. A fair coin is tossed n times.Let X be the no. of times that heads comes up.If P(X=4), P(X=5) and P(X = 6) are in A.P. find the value of n.

Profile image of Rohan Anmol
15 Years agoGrade 12
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1 Answer

Profile image of yazali midhun
15 Years ago

for qQ2 ,the format of data is in form of binomial distribution.

as it is case of tossing a coin,P(x=r) =nCr (1/2)n

so nC4,nC5,nC6 are in ap

so n=7 or 14.

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