To determine the probability of getting at least 2 heads in 3 flips of a fair coin, we first need to understand the possible outcomes. When flipping a coin, each flip can result in either heads (H) or tails (T). Therefore, when flipping the coin 3 times, the possible outcomes are:
- HHH
- HHT
- HTH
- HTT
- THH
- THT
- TTH
- TTT
Out of these 8 total outcomes, let’s count how many of them result in at least 2 heads:
- HHH (3 heads)
- HHT (2 heads)
- HTH (2 heads)
- THH (2 heads)
This gives us a total of 4 outcomes that meet our criterion of at least 2 heads (HHH, HHT, HTH, and THH).
Next, we calculate the probability by dividing the number of successful outcomes by the total number of possible outcomes. The probability (P) is calculated as follows:
P(at least 2 heads) = Number of favorable outcomes / Total outcomes = 4 / 8 = 1/2
Therefore, the probability of getting at least 2 heads when flipping a coin 3 times is 1/2 or 50%.