Question: how to calculate your lean body mass vs. fat percentage?
Answer: For instance, if you weigh 200 pounds and have learned that your body fat percentage is 20%, multiply 200 x 0.20. This is your fat in pounds (200 x 0.20 = 40 lbs). Subtract that from your total weight to get your lean body mass; in this case, 200 - 40 = 160lbs of lean body mass!