SOLUTION: A coin is tossed three times. What is the probability of getting A. Two heads and a tail B. At least one head

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Question 1105635: A coin is tossed three times. What is the probability of getting A. Two heads and a tail B. At least one head
Answer by math_helper(2461) About Me  (Show Source):
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A. P(2 H and 1 T) = P(one T) = 3/8 (3 positions for T, 8=2^3 possible outcomes)
B. P(>= 1 H) = 1 - P(no H) = 1 - 1/8 = 7/8
Check:
This problem is short enough to enumerate the outcomes:
TTT (used in B)
TTH
THT
THH (A)
HTT
HTH (A)
HHT (A)
HHH