Sum Of Multiples
Given a number, find the sum of all the unique multiples of particular numbers up to but not including that number.
If we list all the natural numbers below 20 that are multiples of 3 or 5, we get 3, 5, 6, 9, 10, 12, 15, and 18.
The sum of these multiples is 78.
This exercise requires you to process a collection of data. You can simplify your code by using LINQ (Language Integrated Query). For more information, see this page.
A variation on Problem 1 at Project Euler http://projecteuler.net/problem=1
Submitting Incomplete Solutions
It's possible to submit an incomplete solution so you can see how others have completed the exercise.