Réponse :
X = 1/12 Y = 5/12
Explications étape par étape :
1. X = 1 - ( 2/3. + 1/4. ) = 1 - ( 2x4/3x4 + 1x3/4x3 ) = 1 - ( 8/12 + 3/12 ) =
1 - ( 11/12 ) = 12/12 - 11/12 = 1/12
Donc X = 1/12
Y = (3 - 5/2) / (1 + 1/5) = (18/6 - 5x3/2x3) / (5/5 + 1/5) = (18/6 - 15/6) / (6/5) =
(3/6) / (6/5) = (1/2) / (6/5) = (1x5/2x5) / (6x2/5x2) = (5/10) / (12/10) = 5/12
Donc Y = 5/12