The fictional countries ‘Bookland’ and ‘Musicland’

Did you know about the fictional countries "bookland" and "musicland" 😆 #books #funfact #trivia #countries

Notes & corrections

They usually include a check digit — a final digit used to help detect simple mistakes, like typing one number wrong or swapping two digits. For card numbers, this is commonly checked using the Luhn algorithm. And this idea shows up in many other places too: ISBNs on books, barcodes on products, bank numbers, ID numbers, and more. Just a small example of everyday math! #science #mathisfun #computerscience #funfact