Argh! Not story problems!!!

I hate having to ask two questions in a row, but this story problem is killing me. I've got the answers to the first two parts of the question (I think) but the last part is the one I'm having difficulties with.

*Lauren is competing in her town's cross-country competition. Early in the event, she must race from point *A* on the Greenbriar River to point *B*, which is 5 mi downstream and on the opposite bank. The Greenbriar is 1 mi wide. In planning her strategy, Lauren knows she can use any combination of running and swimming. She can run 10 mph and swim 8 mph. 1) How long would it take if she ran 5 mi downstream and then swam across? 2) Find the time it would take if she swam diagonally from A to B. 3) Find *x* so that she could run *x* miles along the bank, swim diagonally to B, and complete the race in 36 min. (Ignore the current in the river)*

Anyone care to help me out with this one? It would be very much appreciated!!!