Joe Has a Lawn Mowing Job

Short Answer

Joe has a lawn mowing job. If he completes the work he earns $40. But there is a 30% chance it may rain, in which case he won't finish the job. He can pay Jane $20 to help him and ensure that he finishes the job. If X is the amount Joe will get if he does not get Jane to help, calculate E(X) and thus decide whether Joe should hire Jane or not. (If it rains, assume Joe will make no money and if Joe hires Jane assume they will be able to finish the job before it rains. Enter your answer exactly as a,b where a is an integer representing E(X) in dollars (no units), and b is either "yes" or "no" answering the question "should Joe hire Jane?", separated by a comma.