Someone over at Yahoo once described a reasonable interpretation of the ages in Genesis. In this scenario the ages of adults are given as the number of months since attaining adulthood. Since adulthood is 12 years, someone who marries and has children at 75 "years" of age is not 6 years old as is the case if the years are really months, and not a geriatric case if the years are actual years, but 12 + 75/12 years old, or about 18, perfectly reasonable.
Without looking this up, didn't Methusalah live to be in the 900's or so? Using this approach, Methusalah would have been around 87 years old at the time of his death.
A literal Biblical interpretation might not embrace this approach.
--Percy
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