Exercise · ZW-RANDOM-VARIABLE-008 · ★★☆ Intermediate
Two fair coins are tossed and \(X\) is the number of heads. Compute \(P(X\ge 1)\).
Choose one option.
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- A. 3/4
Explanation
The event \(\{X\ge1\}\) is the complement of \(\{X=0\}=\{\text{TT}\}\): \(1-\tfrac14=\tfrac34\).
Review the concept: Random variable
A random variable \(X\) is a function that assigns a real number to each outcome of the sample space \(\Omega\) of a random experiment.
\[X:\Omega\to\mathbb{R}\]
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