This is an interesting problem . I forgot where i read this .. perhaps somewhere on the net
Let his age be D
Diophantus's stages of life :
childhood life - 1/6D
His youth - 1/12 D
Before marriage - 1/7 D
After marriage before birth of child - 5
Child's age when child dies - 1/2 D
Mourn for another 4 years , before he dies .
So how old is this fella ?
Solve for D then .