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View story Additional Abacus Resources 6 / 2 http://www.ee.ryerson.ca/~elf/abacus/afurther.html Submitted by joserra 60 months, 1 day, 20 hours ago Do you want to exercise your mind? Stop using your calculator! Tags: abacus comment (0) | Category: Tech stuff | Add joserra as a source Comments Votes (my sources) Votes (Everyone) Add your comment Add your comment If you already have an account, sign in: Email address: Password: If you don't, just complete these fields: (or join coRank for free) Your name: Your site: (optional) Your comment: (You have up to 5000 characters left) Can you see the 5 most prominent letters/numbers in this image? (case insensitive) Please enter them here: « go back

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