Answer:
The contract expected value is 3,540
Step-by-step explanation:
we multiply each possible outcome by their probability of occur.
sink the piers into bedrock : (600) x 10% = (60)
sink the piers normally: 4,000 x 90% = 3,600
Net 3,540
It is important to always have all the probabilities add up to 100% in order to this method to work.