Question 890716
There are 8 different outcomes:
HHH
TTT
HTT
THH
THT
HTH
TTH
HHT
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The probability of getting any certain 1 of
these ( such as THT ) is: 
{{{ (1/2)*(1/2)*(1/2) = 1/8 }}}
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Looking at the list, there are 3
different ways to get 2 heads
( and obviously 1 tail )
THH
HTH
HHT
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The probability of getting ANY of these
outcomes is {{{ 3/8 }}}
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This is:
( THH ) OR ( HTH ) OR ( HHT ) which is:
{{{ 1/8 + 1/8 + 1/8 = 3/8 }}}