perplexus.info :: Probability : How often does he lie?

How often does he lie? (Posted on 2004-07-02)

In the "Not-always-lying politician" problem, what's the probability that a particular sentence is true?

See The Solution Submitted by Federico Kereki

Rating: 2.5000 (4 votes)

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Given answer is wrong!

| Comment 6 of 9 |

Let p be the probability of a true statement. The probability that the next statement is true is (p/2)+(1-p). That has to equal p.

(p/2)+(1-p)=p

1-(p/2)=p

1=3p/2

p=2/3

Therefore, the probability of a true statement is 2/3.

Posted by Math Man on 2012-05-16 09:25:43

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