math Published July 11, 2010 at 122 × 96 in Simple tricks for doing arithmetic in your head ‹ PREVIOUS --- ‹ PREVIOUS --- Sharing is Caring: Share on Facebook (Opens in new window) Facebook Share on X (Opens in new window) X Email a link to a friend (Opens in new window) Email More Share on Pinterest (Opens in new window) Pinterest Share on Mastodon (Opens in new window) Mastodon
