An ancient mathematician's tombstone is engraved with the following words: "Passerby, here is my life experience. If you are interested, you can calculate my age: 1/7 My life is a happy childhood. After my childhood, I spent 65,438+0/4 time learning knowledge. Afterwards, I got married. Five years after marriage, I felt very happy to have a son. Unfortunately, my children spend only half as much time in the world as I do. After my son died, I spent four years in sorrow and ended my life. "

According to the hint on this tombstone, can you calculate the life span of this ancient mathematician?

x/7+x/4+5+x/2+4=x

x=84

He lived to be 84!