<PRE><B>Question 129029</B>
Use a diagram to list the sample space showing the possible arrangements of heads and tails when four coins are tossed.
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There are 2^4=16 possible outcomes:
4 heads----one way
3 heads----4 ways
2 heads----6 ways
1 head-----4 ways
0 heads----1 way
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Then use the sample space to find the probability that 
a. all four coins come up heads : 1/16
b. exactly two coins come up heads : 6/16
c. exactly three coins come up tails : 4/16
d. at most two coins come up heads: (1 + 4 + 6)/16
e. at least two coins come up heads: (6 + 4 + 1)/16 
f. no more than three coins come up tails: 1 = (1/16) = 15/16
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Cheers,
Stan H. 
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