Hi Steemers! For many people, mathematics can terrify. This list may improve the General knowledge of mathematical methods and speed up mathematical calculations in mind.
Multiplication by 11
We all know that when multiplied by 10 is added to the number 0, and did you know that there is a simple way to multiply two digit number by 11? Here it is:
Take the original number and imagine a space between two characters (in this example, we use the number 52):
Now add the two numbers and write them down in the middle:
Thus, your answer: 572.
If when adding numbers in parentheses obtained a two-digit number, just remember the second digit, and unit add to the first number:
– It always fires.
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Sources:
http://bashny.net/t/en/105258