Subtraction flashcards

Why 66 and not 121

The addition page gives 121 cards from the same range, because every pair works there. Subtraction does not: 3 – 8 has an answer, but it is not one this deck is for, so the deck holds only the pairs where the first number is at least as big as the second. That is 11 cards starting from 10, then 10 starting from 9, and so on down to one starting from 0. Added up it is 66 cards, which is a triangle rather than a square.

Eight to a sheet is 9 sheets and 18 pages counting the backs. The card is 95 by 69.3 mm, both sides at 64 pt.

The minus sign

The cards are set with a hyphen rather than the typographic minus sign. That is a deliberate downgrade: the proper minus sign is not in the character set this press writes into a PDF, and a character the file cannot carry comes out as a question mark. A worksheet uses a hyphen anyway.

Printing it with the addition deck

They are separate files. If you want them mixed, print both and shuffle the cut cards together, or paste your own pairs into the box on the flashcard maker page, which will take whatever mixture you like.

The file

24,970 bytes over 18 pages, black only, PDF.