bonjour
premier jour + dernier jour = 2/5 + 1/6 = 12/30 + 5/30 = 17/30
second jour = 13/30
K = 5/4 - 2/3 x 9/16
= 5/4 - 18/ 48
= 60/48 - 18/48 = 42/48 = 7/ 8
L = 5/7 + 1/7 x ( 5 + 1/2)
= 5/7 + 1/7 x ( 10/2 + 1/2)
= 5/7 + 1/7 x 11/2
= 5/7 + 11/ 14 = 10/14 + 11/14 = 21/14 = 3/2