This proves that the KJV is not perfect. In Acts 15, James quoted a prophecy in Amos 9:12. It matches the translation found in the Septuagint. The KJV is different.
Amos 9:12 in Acts 15 (KJV)
That the residue of men might seek after the Lord, and all the Gentiles, upon whom my name is called, saith the Lord, who doeth all these things. Acts 15:17
Amos 9:12 in the Septuagint
That the remnant of men, and all the Gentiles upon whom my name is called, may earnestly seek [me], saith the Lord who does all these things. Amos 9:12
Amos 9:12 in the KJV
That they may possess the remnant of Edom, and of all the heathen, which are called by my name, saith the LORD that doeth this. Amos 9:12