Back in the day, 70 years was the nominal life span of a human being. Your mileage may vary.
Nowadays, threescore years and ten is an archaic and/or poetic way to express the age of 70.
From The Bible:
The days of our years are threescore years and ten;
and if by reason of strength they be fourscore years,
yet is their strength labor and sorrow;
for it is soon cut off, and we fly away.
-- Psalm 90:10
And from that Scottish play by Shakespeare, as spoken by an old man:
Threescore and ten I can remember well:
Within the volume of which time I have seen
Hours dreadful and things strange; but this sore night
Hath trifled former knowings.
-- Macbeth II.iv
The good Lord willin' and the creek don't rise, this humble noder shall make it there and beyond.
a moment in wertperch's nodeshell challenge