Exercise · ZW-PROBABILITY-MASS-FUNCTION-008 · ★★☆ Intermediate
\(X\) takes the values 0, 1, 2, 3 with masses 0.1, 0.3, 0.4, 0.2. Compute \(P(1\le X\le 2)\).
Choose one option.
Show answer
- C. 0.7
Explanation
Add the masses at 1 and 2: \(0.3+0.4=0.7\). The values 0 and 3 are outside.
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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- ZW-PROBABILITY-MASS-FUNCTION-007 Which statement about a probability mass function is correct?
- ZW-PROBABILITY-MASS-FUNCTION-009 Let p(x)=(tfrac12)^x for x=1,2,3,dots. Compute the probability that X is even.
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