I won't do it for you but I'll try to explain it better than your teacher did if that's your problem, Mi Hijito.
Multiply each possible dollar profit by the probability of it occurring. That's the "partial expected value" of that portion of the universe of possibilities for that project. When you've done all the multiplications for one project, you've got a complete set of partial expected values. Add them up and you have the "total expected value" for the project.
Do that for all the projects you're considering. (Two in this case.) By visual inspection you can see which one has the largest expected value.
But that was the easy part. Which one you choose depends on the strategy dictated by your financial status and your comfort level in taking risks. For example, if the net worth of your entire company is only $80,000, you probably would not choose to pursue either of these projects because you simply could not afford to take the chance of losing $50,000, no matter how slim a chance it is.
But if the company's net worth is ten million dollars, you'd probably just pick the project with the greatest Total Expected Value. If you follow that strategy consistently because you can afford it, then statistically, in the long run you'll come out ahead of companies that follow any other strategy.
There are other strategies that would be used by companies that fall in between these extremes. One is "maximin" (short for "maximize the minimum"), which is to look at the worst possible outcome of each project and choose the one whose worst possible outcome is the "least bad."
Your textbook should teach you all the other strategies.
Good luck.
