perplexus.info :: Probability : Spider and Fly

Spider and Fly (Posted on 2003-11-25)

A spider eats 3 flies a day. Until the spider fills his quota a fly has a 50% chance of survival if he attempts to pass the web.

Assuming 5 flies have already made the attempt to pass, what is the probability that the 6th fly will survive the attempt?

See The Solution Submitted by Ravi Raja

Rating: 3.6250 (8 votes)

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Answer

| Comment 20 of 21 |

The required probability that the 6th fly will survive the attempt is 3/4.

Posted by K Sengupta on 2009-02-15 15:36:15

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