Question 1105635

A.   P(2 H and 1 T) =  P(one T) = <b>3/8</b>      (3 positions for T, 8=2^3 possible outcomes)
B.   P(>= 1 H) = 1 - P(no H) = 1 - 1/8 = <b>7/8</b>

Check:
This problem is short enough to enumerate the outcomes:
TTT    (used in B)
TTH   
THT
THH   (A)
HTT
HTH   (A)
HHT   (A)
HHH