In this post we will give a small introduction about how to use few rules to enhance the speed of mathematical calculations using your mind...

The 1st advice is to try to calculate every thing in your mind even if you can do the same with few click on the calculator to motivate your mind to focus on these mathematical operations..

We will focus in this post in Multiplication Easiness Rule: (*)

If you have 2 numbers multiplied like 150*100 what you do is just adding the 00 beside the 150 and you get 150 00 so it is easy operation, this is what we will try here is to convert any number into 2 numbers (or more) where the biggest number contain zero(s) so the operation become easier..

Let's take the example of 17*3 we will convert 17 into (20-3) and multiply it with 3 so the result : 20 * 3 - 3 * 3 = 60 - 9 = 51

Let's complicate it more:

43*8 = (40+3)*8 = 40 * 8 + 3 * 8 = 320 - 24 = 344

//it could be also done by 50-7 but 40+3 is easier in calculations..

Here is some other examples:

300 * 56 = 300 * (50+6) = 3000*5 + 300*6 = (3*5)000=15000+ (3*6)00 =16800

109 * 97 = 109 * (100-3)=109 00 - 109*3 =10900 - 327= (10500 + 400-327)=10573

//here we chose to do it 109*(100-3) as easier than (100+9)*97

77*37 = (80-3) * (37) = ...

33*66= (33*(70-4)) =...

I hope these simple rules make the multiplication as easy as you can do it inside your mind without the need to use the calculator :)

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