I have a list of numbers:

Code:
100,125,150,175,200,225,250,300,350,400,450,500,600,700,800,900,1000
I do some maths and get a result. I need to workout somehow which one of those numbers above is closest to the RESULT number.

For example if the result was 620 it would be closer to 600 but if it was 678 it would be closer to 700.

Any suggestions?