<PRE><B>Question 1026945</B>
A coin is tossed 4 times and the sequence of heads and tails is observed. 
A: How many different outcomes are possible?:: 2^4 = 16
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B: How many different outcomes have exactly 3 tails?:: 
If 3 tails then 1 head:: Ans: 4
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C: How any different outcomes have at least one tail?
All but 4 heads:: Ans 15
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Cheers,
Stan H.
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