The #3 is the in the ten thousand's place, so that's the number you are rounding. You now look to the place to the right of the 3, which is the thousand's place and is a 1. In order for a number to go up, the number to the right has to be greater than 5. If it's not, then the number you are rounding stays the same. So in this case, the 1 is less than 5, which makes the 3 stay the same. While everything to the right of the number turns into 0s, everything to the left (of the number you are rounding) stays the same. Your new answer would be 430,000. Hope that helps and makes sense. (:
