private static ScaleFactor Reduce (int numerator, int denominator)
{
int factor = 2;
while (factor < denominator && factor < numerator) {
if ((numerator % factor) == 0 && (denominator % factor) == 0) {
numerator /= factor;
denominator /= factor;
} else {
++factor;
}
}
return new ScaleFactor (numerator, denominator);
}