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A few years ago I visited a ‘developing country’ where a labourer would work a long day for one US dollar. This income had to cover a family’s shelter, clothing, food, transport, educational and medical costs. I am acutely aware that a very large part of the world’s population lives in poverty (including many in the ‘developed world’) and, for many of them, a good education provides a means of escape … a way of supporting their family.

Although governments and organisations may provide access to the Internet, many poor families throughout the world (including the ‘developed world’) and many schools in developing countries cannot afford the educational materials that are offered on commercial sites.

This website aims to provide all visitors with free access to a store of useful resources in the hope that students may be inspired (and helped) to excel in mathematics.


If you benefit from this site and can afford to support this ministry, any donation that you could make would be very welcome.

Any constructive feedback (or suggestions) that you can provide would also be appreciated.

I enjoyed your presentation and no it wasn’t too long. Each subtraction algorithm has its merit as you demostrated, but after learning the “one up and one down” method, I’m employing it because of its speed and ease of usage. Even my wife, who hates mathematics with a passion, thinks it’s too easy. I look forward to your future presentations on both multiplication and number theory. I read an introduction text book some twenty five years ago on number theory by Oystein Ore who taught at Yale for better than twenty years. So in closing, please produce these lectures and the longer the better. Thanks.
Dennis Bell (on a CCM YouTube video about How to Subtract (Large) Numbers Easily)

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