Mental Arithmetic 125×56

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Jun 26, 2011 21:10
Although I am not sure how it will be useful in the future, this kind of training is popular among the top schoolchildren in Japan. They quickly do multiplications in their head.

36×25
125×56

Once you learn the method, it is not difficult. However, even if a schoolchild figures out the method on his own, he is perhaps inferior to Gauss, to say nothing of those who are simply taught it by teachers.