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Source: — Problem Solving |
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by parallel_chase » Mon Aug 25, 2008 10:37 am
2 heads and 1 tail out of 3 flips

HHT = 1/2*1/2*1/2 =1/8

THH =1/8

HTH =1/8

I/8+1/8+1/8 =3/8=.375

Hope this helps.
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by gmattester » Mon Aug 25, 2008 11:56 am
parallel_chase wrote:2 heads and 1 tail out of 3 flips

HHT = 1/2*1/2*1/2 =1/8

THH =1/8

HTH =1/8

I/8+1/8+1/8 =3/8=.375

Hope this helps.
Thanks Chase ..
You r best....
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by sg4931 » Tue Sep 09, 2008 3:31 pm
There is an easy formula to solve such problems

• The probability of getting exactly k results out of n flips is: nCk/2^n

3C2/2^3 = (3!/(2! * 1!))/8 = (3!/2!)/8 = 3/8
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