2 Samuel 5 4
David was thirty when he became king, and he reigned for forty years.
Compare with other 3 random translations
KJV 2 Samuel 5:4David was thirty years old when he began to reign, and he reigned forty years.
YLT 2 Samuel 5:4A son of thirty years is David in his being king; forty years he hath reigned;
GW 2 Samuel 5:4David was 30 years old when he became king, and he ruled for 40 years.