bonjour
3 p + 1 /6 + 1/6 + 2 /6 = 1
3 p + 4 /6 = 1
3 p + 2 /3 = 1
9 p /3 = 3/3 - 2 /3
9 p = 1
p = 1/9
1/9 + 4 /6 + 2 /9
= 2/18 + 12/18 + 4 /18
= 18/18 = 1
