Let A, B, and C be three events such that C ⊆ B ⊆ A. Let a = P(A), b = P(B), and c = P(C).

(i) Calculate the probabilities P(A − B), P(A − (B − C)), P((A − B) − C)

in terms of

a, b,

c. What do you observe?

(ii) Obtain a numerical answer to the result in (i) for a = 1∕2, b = 1∕4, c = 1∕6.