1. The problem: A coin is tossed four times, and the result (heads or tails) of each toss is recorded. We need to find how many different sequences of heads and tails are possible. 2. Each toss has 2 possible outcomes: heads (H) or tails (T). 3. Since the coin is tossed 4 times, the total number of sequences is the product of the possibilities for each toss. 4. Therefore, the number of sequences is $$2 \times 2 \times 2 \times 2 = 2^4$$. 5. Calculate $$2^4 = 16$$. 6. Thus, there are 16 different possible sequences of heads and tails when a coin is tossed four times.