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Heads / Tails Sequence Problem

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by liferocks » Wed Apr 14, 2010 5:00 pm
we can rephrase the question as selecting 12 blank spaces from 37 blank space
the number of ways it is possible are 37C12
no arrangement is involved as all heads are of the same coin hence identical
now 37C12=37C25 rule nCr=nC(n-r)
hence the ans will be
[spoiler]D
The number of different possible sequence of heads and tails that contain 25 heads that can result from tossing a coin 37 times
[/spoiler]
Can you please confirm the ans..I am very weak in this type of question cannot say the ans is correct with full confidence :(
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by Fiver » Wed Apr 14, 2010 7:13 pm
liferocks wrote:we can rephrase the question as selecting 12 blank spaces from 37 blank space
the number of ways it is possible are 37C12
no arrangement is involved as all heads are of the same coin hence identical
now 37C12=37C25 rule nCr=nC(n-r)
hence the ans will be
[spoiler]D
The number of different possible sequence of heads and tails that contain 25 heads that can result from tossing a coin 37 times
[/spoiler]
Can you please confirm the ans..I am very weak in this type of question cannot say the ans is correct with full confidence :(
Nice job. You rock!!!
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