Question 1180783
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It is mathematical expectation


    E = {{{sum(X*P(X), X=0, 4)}}} = 0*P(0) + 1*P(1) + 2*P(2) + 3*P(3) + 4*P(4) = 0*0.10 + 1*0.15 + 2*0.20 + 3*0.35 + 4*0.20 = 2.4.    <U>ANSWER</U>
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Solved.


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Every student must know how to calculate it.


It is a basic, &nbsp;like &nbsp;&nbsp;2*2 = 4 &nbsp;&nbsp;in &nbsp;&nbsp;Arithmetic.