Muhammad Farooq-i-Azam: Independence of Three Events with Solved Example

Solved Problem: In an experiment with equiprobable outcomes, the partition is S={1, 2, 3, 4}, P[s]=1/4 for all s in S. Are the events A1={1, 3, 4}, A2={2, 3, 4} and A3 = phi mutually independent?

Probability and Stochastic Processes -- A friendly introduction for electrical and computer engineers by Roy D. Yates and David J. Goodman