Different Dates on Different Documents

My Grandfather Enrique Chavez, died 25 Feb 1960. I know this because I have a photograph of his tombstone. On this same tombstone, it shows that he was 92 years old when he died. Enrique was married twice, first to Julia Zarate and then to Genoveve Romero. I have the 1904 marriage documentation from the church. Here is where things get strange. In this document, he is listed as a widower and his first wife is listed, Julia Zarate. His age is given as 45! His new wife Genoveva Romero, was 17 years old. I also have a copy of the Mexican 1930 Census, where his little family is documented correctly. His age however, in this document is listed as 60! The bottom line, I have three dates thusly;

25 Feb 1960 - 92 years old at death = 1868
1 Feb 1904 - 45 years old at wedding = 1859
15 May 1930 - 60 years old at Census = 1870

Any ideas?