One pound of body fat is equivalent to approximately calories

It has been proven that the caloric equivalent of one pound of body fat is 3500 calories approximately. One pound is equal to 454 grams and one gram of pure body fat contains 8.7 to 9.5 calories. Considering the fact that body fat tissue is 87% pure fat, we can calculate that one pound of body fat contains approximately 3.436 to 3.752 calories. 

True to the fact it is actually false