Solution: Each coin toss has 2 possible outcomes "Head" and "Tail". So if we flip a coin four times, the number of possible outcomes are:
[tex]2^{4} = 16[/tex] outcomes.
Let H denotes the Head and T denotes the Tail, then the 16 possible outcomes are enumerated below:
HHHH, HHHT, HHTH, HHTT, HTHH, HTHT, HTTH, HTTT,
THHH, THHT, THTH, THTT, TTHH, TTHT, TTTH, TTTT
