Bonjour,
1) Voir pièce jointe
2) P(A ∩ T) = 1/3 * 3/4 = 3/12 = 1/4
3) P(T) = 1/3 * 3/4 + 2/3 * 1/2
= 3/12 + 2/6
= 3/12 + 4/12 = 7/12
