How to round an integer to the nearest hundred in Javascript? [duplicate]

Question

Let's say I have a number

let x = 890

and I want it to be rounded to 900

and if the number is 820 then it should be rounded to 800.

Let's also assume the input number (x) will always be an integer,

I know that we can solve this by manually checking if it is greater than 50 or not, but is there a simpler solution? preferably by recursion in javascript.

Answer 1

Just of the top of my head:

Take any number, divide it by hundred, round the number with Math.round(), multiply by 100 to get your desired number.

const roundNumber = (num) => Math.round(num/100) *100

Answer 2

If you want to round up and down.

Math.round(number/100)*100

For more indepth and also a comparison with Math.ceil() check out this link:

How to round up to the nearest 100 in JavaScript