Add all the natural numbers below one thousand that are multiples of 3 or 5.

Seems simple enough? Here’s my brute force way of answering it (using Python):

[sourcecode language=”python”]
n = 1
sumTo = 0

while n < 1000:
if (n%3 == 0) or (n%5 == 0):
sumTo = sumTo + n
n = n + 1
else:
n = n + 1

print (sumTo)
[/sourcecode]
How would you solve it?