Old Testament readings use the Septuagint , the Scripture the apostles quoted. Masoretic numbering shown for reference.Learn why
KJV

1 Kings 7:31

And the mouth of it within the chapiter and above was a cubit: but the mouth thereof was round after the work of the base, a cubit and an half: and also upon the mouth of it were gravings with their borders, foursquare, not round.

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