Here, I offer as many solved problems as I can get my hands on for you. Please send me email with your suggestions. This is a crib sheet that I created. Could be good. Probability Crib Sheet UCSD ECE109 Winter 1999 Exams with solutions are available.
Most exams cover some probability and introductory random variables.
Exam 1 Exam 2 Exam 3 Homework problems have solutions, but unfortunately, no statement of the problem. The problem assigment is listed, so if you can get your hands on the Yates text , then you can see the statement of the problem. These links I borrowed from Prof. Ramesh Rao's old ECE109 web page. Some have solved problems, other demonstrate interesting aspects of common problems such as the Central Limit Theorem, or the Monty Hall Problem.