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by romitvsingh » Tue Nov 22, 2011 12:25 am
Ten coins are tossed simultaneously. In how many of the outcomes will the third coin turn up a head?

(A) 210
(B) 29
(C) 3*28
(D) 3*29
(E) None of these

pls explain in detail
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by shankar.ashwin » Tue Nov 22, 2011 12:32 am
Total possible outcomes are 2^10 = 1024.

Now in half the cases the 3rd coin will have a head and the other half will have tails.

So 512 (2^9) cases head and 512(2^9) cases tail. E IMO
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by vishal chugh » Tue Nov 22, 2011 3:29 am
each coin can have two outcomes either head or tell... so if u particular any outcomes. in the case , 3rd as head or tell. other 9 outcomes can be both head or tell. so total of 512 outcomes are there in which third outcome is head or tail
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