Exodus 1:2-6

"Reuben, Simeon, Levi, and Judah, Issachar, Zebulun, and Benjamin, Dan and Naphtali, Gad and Asher. And all the souls that came out of the loins of Jacob were seventy souls: and Joseph was in Egypt already. And Joseph died, and his brethren, and all that generation."

Regarding the number "seventy," see comments on this under Genesis 46:7. All of the alleged "difficulties" regarding "the seventy," and Stephen's "seventy-five" (Acts 7:14) disappear altogether when it is seen as evident that different frames of calculation were used, some included the family of Joseph (who were already in Egypt), and some evidently included children of Joseph born after Ephraim and Manasseh, some included wives of sons, or wives of grandsons, or counted certain deceased ones, or excluded them ... etc. All Biblical references to this event are absolutely correct. The Septuagint (LXX) reference to "seventy-five" includes five of Joseph's posterity not included in those who "went down into Egypt with Jacob."[3] Also, the number "seventy" is symbolical, and is designed to show the completeness of the Hebrew migration to Egypt.