How old was Lamech when he died?
Lamech lived 777 years, from 3130 BC to 2353 BC.
Lamech died at 777. The chart places his birth at 3130 BC and his death at 2353 BC, on the Ussher chronology it follows. Father of Noah; died five years before the Flood. (Gen. 5:25-31)
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A date means more beside its neighbours. The chart puts this answer in place next to everything happening around it — biblical and world history across the same six thousand years.
Now see where it sits
Everything on this page has a place on one 45×37″ chart — and once you can see what came before and after it, it stops being a fact and starts being a story you can follow.