# Remainder in JavaScript

having trouble with the remainder operator concept

i dont get it… start from the beginning

example: var remainder = 11 % 3;

what’s going on here?

please give a few more examples using the remainder operator and explain

kindly explain so its clear : )

thank you!!

In long division we have four parts to the overall expression.

``````Dividend   =>  the number being divided
Divisor    =>  the number being divided by
Quotient   =>  the whole number result
Remainder  =>  the non-divisible amount
``````

Take `11` over `3` from your example…

``````11 / 3     =>  3.66..
``````

but when we take `0.66..` and resolve it to a rational number (all repeating decimals are rational numbers) we get `2/3`.

Now multiply `2/3` by the divisor, `3`, and we get `2`. Thus, 11 modulo 3 is 2.

``````11 % 3     =>  2
``````

Now consider the whole number quotient, `3`,

``````3 * 3      =>  9
11 - 9     =>  2
``````

Again, remainder of 2.

We can use the remainder as a signal of non-divisibility. If the remainder is not zero, then the dividend cannot be divided evenly by the divisor. We now know with certainty that 3 does not divide into 11. There will always be a remainder.

From what we’ve covered above we have a simple formula…

``````D - qd = R
``````

D is the Dividend; d is the divisor; q is the quotient; and, R is the remainder. This holds for integers or floats though in JavaScript, float remainders are not supported. We must look at this from the integer perspective.

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