Is 21 Divisible By 3?
In this quick and easy guide, we'll work out whether 21 is divisible by 3. There are some simple rules we can follow to decide whether one number is divisible by another without ever needing to even do the division!
First up, let's clarify what we mean by "21 is divisible by 3". What we want to check is whether 21 can be divided by 3 without any remainder (i.e the answer is a whole number).
When checking if a number is divisible by 3, the easiest way to check this is to sum up the digits in 21 and if that resulting number is divisible by 3, then 21 is too.
2 + 1 = 3
We can see that the sum of the digits in this case is 3 and this number IS divisible by 3, which means that 21 is also divisible by 3.
Another way you can figure out if 21 is divisible by 3 is by actually doing the calculation and dividing 21 by 3:
Since the answer to our division is a whole number, we know that 21 is divisible by 3.
Hopefully now you know exactly how to work out whether one number is divisible by another. Could I have just told you to divide 21 by 3 and check if it is a whole number? Yes, but aren't you glad you learned the process?
Give this a go for yourself and try to calculate a couple of these without using our calculator. Grab a pencil and a piece of paper and pick a couple of numbers to try it with.
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"Is 21 Divisible By 3?". VisualFractions.com. Accessed on November 26, 2021. http://visualfractions.com/calculator/divisible-by/is-21-divisible-by-3/.
"Is 21 Divisible By 3?". VisualFractions.com, http://visualfractions.com/calculator/divisible-by/is-21-divisible-by-3/. Accessed 26 November, 2021.
Is 21 Divisible By 3?. VisualFractions.com. Retrieved from http://visualfractions.com/calculator/divisible-by/is-21-divisible-by-3/.