Probability by Sheldon Ross is pretty good. I also referred a book: https://www.amazon.com/Probability-Statistics-Reliability-Queueing-Applications/dp/0471333417 for a course. The author has taught everything from basics to stochastic processes, etc.
If you really like this stuff, I would highly recommend two textbooks:
For the communications topics, reliability, optimization etc, ditch Leon-Garcia and pick up this book by Trivedi
If you're interesting in Machine Learning like I am, then this book by Bishop is fantastic. You can find both in the Engineering library I believe.
Looks like you can solve this one by hand. It has been a while since I've done this, so I forget the specifics. Here is the best book I know of on this subject material: http://www.amazon.com/Probability-Statistics-Reliability-Queueing-Applications/dp/0471333417/ref=cm_cr_pr_product_top Everything you will need to know is in there. You could also try looking at the author's slides, which are also helpful: http://people.ee.duke.edu/~kst/ECE257/