The rate is different for everyone. Most people lose 1-2 pounds on average per week, but you don't want to rush it. Your body will adjust to your new weight as long as it has time to. That way, your skin will have time to contract so that it isn't baggy as you shed the pounds. Mainly, if you excercise the way that you find comfortable and you lose 3 pounds, great. Just don't push yourself to lose more than your body can handle at a time. It is normal to want to lose it all at once, but that isn't the healthiest route to take.