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A fair coin is tossed three times and the outcomes are noted. What is the probability of getting exactly two heads?
Explanation
When a fair coin is tossed three times, the total number of possible outcomes in the sample space is 2^3 = 8. These outcomes are {HHH, HHT, HTH, HTT, THH, THT, TTH, TTT}. To find the probability of getting exactly two heads, we identify the specific outcomes that satisfy this condition. The favorable outcomes are {HHT, HTH, THH}, totaling three distinct possibilities. The probability is calculated by dividing the number of favorable outcomes by the total number of outcomes in the sample space. Therefore, the probability of obtaining exactly two heads is 3/8. This can also be calculated using the binomial distribution formula (n choose k) / 2^n, where (3 choose 2) / 2^3 equals 3/8.
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