(a) P = P(A) × P(B) × P(C) = 0.4 × 0.3 × 0.2 = 0.024

(b) We use the notation P( A⁻) to mean "the probability that A will not occur". So:

P = P( A⁻) × P( B⁻) × P( C⁻) = 0.6 × 0.7 × 0.8 = 0.336

(c)

(d) P = 1 − { P( A⁻) × P( B⁻) × P( C⁻) } = 1 − 0.336 = 0.664