Number syetem tricks by5

Division rule by 5

A last digit of a number must be 0 or 5 then the whole number must be devided

Ex:-
81637985÷5

Ans) 5÷5=1

So 81637985 must be devided by 5

Practice
1)26562970
2)6441875
3)816572980

You probably already know what a number system is - ever hear of binary numbers or hexadecimal numbers? Simply put, a number system is a way to represent numbers. We are used to using the base-10 number system, which is also called decimal. Other common number systems include base-16 (hexadecimal), base-8 (octal), and base-2 (binary).
Before we get started, let's try a little activity for fun. There are many different ways to represent a color, but one of the most common is the RGB color model. Using this model, every color is made up of a combination of different amounts of red, green, and blue.
You may be wondering how colors relate to number systems. In short, on a computer, any color is stored as a large number: a combination of red, green, and blue. (We'll go into more detail on this later.) Because it's just a number, it can be represented in multiple ways using different number systems.
Your job is to guess how much red, green, and blue is in the background color of the activity below. The values for red, green, and blue can range from 0 to 255.
Feel free to use the various hints provided to help you out. If you don't understand the numerical hints yet, no problem! You can see what your guess looks like using the View Guess button. Right now, it may seem tricky, but hopefully by the end of the article, it will seem easy.