Nikolay Bogdanov-Belsky’s Painting: Mental Arithmetic

Nicholas Bogdanov-Belsky painted the iconic painting “Mental Arithmetic in the Public School of S. Rachinsky” in 1895, which is now considered a classic. Students are trying to figure out how to solve the problem on the blackboard, which is 10²+11²+12²+13²+14²)/365. They also appear to be having a great time. On the other hand, learning is no longer regarded as enjoyable by pupils. Can you come up with a way to solve it without using a calculator?

Ali Kaya


Ali Kaya

This is Ali. Bespectacled and mustachioed father, math blogger, and soccer player. I also do consult for global math and science startups.

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