If a fair coin is tossed two times, the probability that the first or the second toss will be heads is ________ (rounded off to two decimal places).
Correct Answer: 0.75
Solution and Explanation
The probability of getting heads on either toss is:
\( P(\text{first head}) = \frac{1}{2}, \quad P(\text{second head}) = \frac{1}{2}. \)
Using the formula for the probability of either event occurring:
\( P(\text{first or second head}) = P(\text{first head}) + P(\text{second head}) - P(\text{both heads}), \)
\( P(\text{both heads}) = \frac{1}{4}. \)
Thus:
\( P = \frac{1}{2} + \frac{1}{2} - \frac{1}{4} = 0.75. \)
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