SOLUTION: math's youth lasted 1/6 of his life he had first beard in the next 1/12th of his life at the end of the following 1/7th of his life, math got married 5 years from then his son w

Suppose he lived to be N years old.

From his birth until the end of his youth was N/6 years
From the end of his youth until he grew his first beard was N/12 years.
From the time he shaved off his first beard till he got married was N/7 years.
From the time he got married until his son was born was 5 years.
From the time his son was born until his son died was N/2 years
From the time his son died until he died was 4 years.

All that adds up to N



Multiply through by the LCD = 84









He lived 84 years.

Edwin