Exercise · ZW-PROBABILITY-MASS-FUNCTION-005 · ★★☆ Intermediate
With \(p(x)=\tfrac{x}{10}\) for \(x=1,2,3,4\), compute \(P(X\ge3)\).
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- B. 7/10
Explanation
Add the masses of the included values: \(p(3)+p(4)=\tfrac3{10}+\tfrac4{10}=\tfrac7{10}\).
Review the concept: Probability mass function
The probability mass function \(p_X\) of a discrete random variable \(X\) gives, for each value \(x\) it can take, the probability \(P\) that it takes it.
\[p_X(x)=P(X=x)\]
More practice problems: probability mass function
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