Exercise · ZW-PROBABILITY-MASS-FUNCTION-004 · ★☆☆ Basic
Let \(p(x)=kx\) for \(x=1,2,3,4\) and 0 otherwise. What value must \(k\) have?
Choose one option.
Show answer
- D. 1/10
Explanation
We need \(k(1+2+3+4)=10k=1\), so \(k=\tfrac1{10}\).
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.
\[p_X(x)=P(X=x)\]
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