perplexus.info :: Probability : Define a rational function

Define a rational function (Posted on 2024-03-04)

You have coins C1, C2, · · · , Cn. For each k, coin Ck is biased so that, when tossed, it has probability 1/(2k + 1) of falling heads.

If the n coins are tossed, what is the probability that the number of heads is odd?

Express the answer as a rational function of n.

Source: Putnam 2001

See The Solution Submitted by Ady TZIDON

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re: solution @ Ch & KS

| Comment 3 of 5 |

(In reply to solution by Charlie)

Bravo,

There is also an easy analytical solution.

Edited on March 4, 2024, 9:09 pm

Posted by Ady TZIDON on 2024-03-04 21:00:01

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