Princeton Probability

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by givemeanid » Mon Jul 09, 2007 3:37 pm
Total possible outcomes = 2*2*2*2*2 = 32

Possibilities with three tails = 5C3 = 10

Probablity = 10/32 = 5/16
So It Goes

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by lanter1 » Tue Jul 10, 2007 4:09 pm
I believe the answer is 5C3/32 or 10/32=5/16

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by lalitgmat » Wed Jul 25, 2007 1:54 pm
Total Possible Combinations : (H/T)...5times => 2-to-the-power-5 = 32
Favourable Combinations: TTTHH or HHTTT or HTTTH, since coins are being identical, we can not take each above cases as separate ones.
Hence 5C3 is the way TAILs come up.

Prob = 5C3 upon 32

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by blaster » Tue Jun 23, 2009 4:53 am
excuse me for that question,but how you calculate here 5C3?i just forgot the formula.
is it in this way?

5c3= factorial(5)/(factorial(3)*(factorial(5)-factorial(3))?

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by Stuart@KaplanGMAT » Tue Jun 23, 2009 10:55 am
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