A fair coin is tossed three times. What is the probability of at least two heads?
Answer and explanation
Correct answer: D.
- Step 1: List the outcomes with at least two heads: HHH, HHT, HTH and THH. Step 2. That is 4 of 8, so the probability is . **Answer: . Why not the others:** forgets HHH, counts too few outcomes, and is the chance of at least one head.
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