Q: how many calories does the average person burn per day with no exercise?

A: It'll depend on a bunch of things: person's gender, age, health and health history, weight and body-fat percentage, diet and diet history, and the all-important genetics. There's no way to say for certain. The much more important point is that pure calorie counting is a poor approach to losing fat. Not all calories are created equal, and 'burning' twice as many extra calories does not in any way guarantee losing twice as much fat. Instead of focusing on number of calories burned, you need to focus on having a good diet, exercise (preferably with weight training, but definitely some exercise), and slow steady weight loss. A routine that consistently loses you 1 pound per week is much more likely to give you long-term success than some fad diet that loses you 10 pounds in the first week! This is a very important point that is not understood by most people. Please see http://www.mikesfitness.com/content/can-you-lose-3-pounds-a-week and read my fat-loss article for more info.