How many kilograms in as a percentage of body fat?
Percent means 'out of one hundred' so to say that someone's body
is 20% fat means that for every 100kg, 20kg will be fat. If the
person weighs 50kg, 10kg of that is fat. If you know what percent
body fat you are, and how much you weigh, then your mass of fat is
'percent fat divided by 100 then multiply by your mass in kg.'