Question 753909
The chance of hitting oil is 1/40, gas 1/20, and nothing 1 - 1/40 - 1/20 = 1 - 1/40 - 2/40 = 40/40 - 3/40 = 37/40<P>
Multiply each outcome by the probability of each:<P>
1/40 * 425000 + 1/20 * 125000 - 37/40 * 25000 = 10625 + 6250 - 23125 = 16875 - 23125 = -6250.<P>
The expectation is a loss of $6250.00.  
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