Simple math tricks not taught in school
“Well, and how will mathematics help me in my life?” The children in the lessons grumble, and when they grow up, they even forget the multiplication table and reach for the calculator, doing the simplest calculations. But knowing the following mathematical tricks, we would be very interested in school algebra!
Quick mind counting
A quick bill is useful in your daily life - for example, when you need to calculate the amount in the store. One cake costs 30.95, and a cupcake - 23.76. How to find out the amount of the check? Just round the first price to 31, and add to the cost of the cake - it is 54, 76. and now from this amount, deduct 5 kopecks: 54.76-0.05 = 54.71.
Multiplication of 2-digit numbers
To master the rapid multiplication of two-digit numbers, for example in construction calculations, the following mathematical focus will help:
- Each of the multipliers is subtracted from one hundred: 100-91 = 9; 100-93 = 7.
- The resulting differences first add each other: 9 + 7 = 16.
- And then we multiply: 9x7 = 63.
- Subtract the difference from one hundred: 100-16 = 84.
- The resulting number is put at the beginning of the result, and the product of differences is put at the end: 84 and 63 = 8463.
The result: 91x93 = 8463.
Squaring is not an easy task, but only if it does not apply to numbers that end in 5! Simply multiply the 1st digit of the desired number by a digit that is more by 1, and then transfer to the end of the number 25:
For example, 85 ^ 2: 8x9 = 72; 72 we put in front of 25 - we get 7225.
85^2= 7 225.
Rapid division by 2
Mathematical tricks help and quickly divide by 5: multiply the original number by 2, then move the comma one character to the left:
- 234x2 = 468
- 468 » 46,8
i.e. 234/5 = 46.8.
Find the percentage of tip, multiply the complex numbers when calculating the exchange rate and perform other useful mathematical operations will help mathematical tricks from this video:
Pay attention to the following secrets of mathematics, which can greatly facilitate your life and surprise your friends. They just need to remember, this will help you to develop memory activities.
You can master mathematical tricks, master fast counting skills and produce stunning results even at a young age, as this amazing calculator Ilyas Tokhtarkhan proved to the whole country - see for yourself:See also: 5 ways to improve memory