Réponse:
T = 1/7 × 5 + 1/5 × 7+ 1/35
T = 5/35 + 7/35 + 1/35
T= 13/35
W = 2/3 × 4 - 5/4 × 3 - 11/12
W= 8/12 - 15/12 - 11/12
W= - 7/12 - 11/13
W= - 18/13
U= 3/4 × 5 + 2/5 × 4 + 7/20
U= 15/20 + 8/20 + 7/20
U= 23/20 + 7/20
U= 30/20
Y= 1/2 + 4/3 - 5/6
Y= 1/2 × 3 + 4/3 × 2 - 5/6
Y= 3/6 + 8/6 - 5/6
Y= 11/6 - 5/6
Y= 16/6
V= 3 + 5/2 × 2 + 3/4
V= 3+ 10/4 + 3/4
V= 13/4 + 3/4
V= 16/4
Z= 2- 6/7 × 2 + 3/2 × 7
Z= 2 - 12/14 + 21/14
Z= 10/14 + 21/14
Z= 31/14
