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How would I go about solving this problem?

What are the chances of at least $4$ heads if you flip a coin $5$ times

I constructed a tree diagram but I don't think that is correct. The answer I got was $\frac{1}{8}$.

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Each of the $2^5=32$ possible sequences of heads and tails is equally likely. There's one sequence with all heads, and there are $5$ different sequences with four heads, corresponding to the $5$ possible positions of the one tails result. Thus the probability is $(1+5)/32=6/32=3/16$.

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Apply Bernoulli's Formula:

$$\frac{1}{2^5}\left(\binom{5}{4}+\binom{5}{5}\right)$$

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