If you ever dreamed to become a human calculator, the time has come, and you are late. Grab a book or two about the mental arithmetic methods (like "The Trachtenberg Speed System of Basic Mathematics" or "Secrets of Mental Math")(You can do it without books and just with practice, too, but it's less efficient) and start your spaced practice today with this wonder-packed deck of limitless practice cards.
All cards are generated using "Arithmetic Problem Generator (Project APG)". You can download Project APG from here:
https://www.dropbox.com/s/3bil2skcb9gcbnc/APG.xlsm?dl=0
(I have also included this other shared deck here for convenience:
https://ankiweb.net/shared/info/432596766)
(You'd better create a new options group for this deck and set its max reviews to ZERO, or you'll be in trouble...)
(If you like this, say so!)