Roundup using math

Question

I have a amount 100001, i want to round it up to nearest 10000. my expected output after roundup would be 110000.

How to do that using c#??

Answer 1

double c = Math.Ceiling( 100001 / 1000 ) * 1000;

Answer 2

I believe this works given the test case:

double RoundUp(double value, double factor) {
    return Math.Ceiling(value / factor) * factor;
}

Usage:

var answer = RoundUp(100001, 10000);

Answer:

110000