rovshan85 wrote:

What is the probability of getting at least 2 heads in a row on three flips of a fair coin?

We can assume the first two flips are heads (H) and the last flip is tails (T). Thus:

P(H-H-T) = 1/2 x 1/2 x 1/2 = ⅛

The only other way to get two heads in a row would be flipping heads on the second and third flips.

P(T-H-H) = 1/2 x 1/2 x 1/2 = ⅛

Thus, the total probability of getting two heads in a row when we flip a coin three times is 1/8 + 1/8 = 2/8.

Next, we need to determine the probability of getting heads on all three flips.

P(H-H-H) = 1/2 x 1/2 x 1/2 = 1/8.

Thus, the probability of getting at least two heads in a row is 2/8 + 1/8 = 3/8.

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