Answer
See below.
Work Step by Step
By definition, the expected value is the sum of each outcome multiplied by its probability.
Hence here the expected value: $\frac{1}{4}\cdot(30000-3000)+\frac{3}{4}\cdot(-3000)=4500$.
This means that in the long run they are expected to win $4500$ on average per bid on similar bids.
