וַֽיְחִי־נֹ֖חַ אַחַ֣ר הַמַּבּ֑וּל שְׁלֹ֤שׁ מֵאוֹת֙ שָׁנָ֔ה וַֽחֲמִשִּׁ֖ים שָׁנָֽה׃
홍수 후에 노아가 삼백오십 년을 지내었고
Radak on Genesis
ויחי נח, the principal reason why the Torah lists the ages of these antediluvian people is only to enable us to count back to when human history started with the creation of Adam. All such basic historical data are provided both in the Torah and in the Books of the prophets.