# The Divisibility Test of 4

A number is posed to you and you are asked to check if it is divisible by 4. If the number is manageably small, you can divide it by 4 and see if it leaves a remainder. What do you do if the number is quite large? In such cases, you are advised to use a tool called divisibility test. How does it work? Can you tell that a large number is divisible by 4, without actually dividing it by 4? Check out the trick and the math behind it.

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