This is the most trusted repository for old textbooks. Search for "Aritmetica Baldor" on Archive.org. You will usually find high-quality scans available for borrowing or downloading in PDF format. It is non-profit and safe.
Contrary to the popular image of the bearded scholar on the cover (who is actually the Persian mathematician ), the book's author was Aurelio Ángel Baldor de la Vega , a Cuban lawyer and passionate educator. aritmetica baldor pdf