Three-point expectation

Topic: Random variables and distributions · more questions on this topic
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A random variable takes the values 0, 2 and 5 with probabilities 1/2, 1/3 and 1/6. Find its expectation.

Worked answer (click to show)

\mathbb{E} X=0\cdot(1/2)+2\cdot(1/3)+5\cdot(1/6)=4/6+5/6=3/2.