It means: in Diophantu's life, his childhood accounted for 1/6, his youth accounted for112, he spent 1/7 on marriage, gave birth to a child five years later, and his father died four years later, and his life span was half that of his father. This is equivalent to the equation X/6+X/ 12+X/7+5+X/2+4 = X, X = 84, from which we can see that Diophantine died at the age of 84.
Solution: Let the life of Diophantine be x years, and get
1 \ 6x+ 1 \ 12x+ 1 \ 7x+5+ 1 \ 2x+4 = x
25\28x-x=-4-5
-3\28x=-9
x=84