Question 1180289
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<pre>

In the given sample space, count the number of 3-letter words, containing at least one letter H.


This number is 7, so your answer is  {{{7/8}}}.



By the way, this event (getting at least one head) is the complement to the event "no head",


so you can get the same answer by another way . . . 
</pre>


Solved, answered and explained.