Mathematics is the queen of all sciences.

Whether often you go shopping? And whether often you face a problem of calculation of the prices and percent? There is one small mathematical life hack with which the discount in shop can be calculated for couple of seconds and without the calculator.

Even if you were always an excellent student on mathematics and quickly multiplied in mind, it is sometimes difficult to count, for example, 14% of 150. If to consider how at school, then at first it is necessary to calculate one percent, then to increase by 14 … Stop! There is a way easier!

 It's very simple: x% of y = y% of x. In simple terms, 14% of 150 is 150% of 14. And this is equal to 21. Check, it really works with all numbers! Of course, if the large and "inconvenient" number got to you, this cunning will not approach, but this way will be able sometimes to help out you!