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# Exercising mental calculus!

Let's forget paper and calculators this moment! I really enjoy to resolve all kind of calculus only with my mind. I have prepared these simple but powerful mental exercises and a trick i use to do it faster and faster.

37 x 42 , 78 x 36 , 342 x 18 ,

To turn it easier ,simply do it like this in 37 x 42: (35 x 40) + ( 2 x 40 ) + ( 2 x 37 ) , doing this you will reduce the time you waste solving problems, because you work with lower numbers.

78 x 36 can be: (70 x 30 ) + (8 x 30 ) + ( 6 x 78 ) , have you understood? Resolve the calculus and you will see that the results will come really fast.

Just use this technique on the way you think that is better

Note by Marcos Paulo Martins
3 years, 6 months ago

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Why is this calculus?

- 3 years, 6 months ago