weighted value of a variable is the expected value of that variable.
If a firm's decision makers think, for example, that there is a
10% probability that next year's profits will be $100,000; a 55% probability
that they will be $200,000; and a 35% probability that they will be $300,000,
then the expected value of profits is:
0.10 x ($100,000) + 0.55 x ($200,000) + 0.35 x ($300,000)