(b) This conversion of 98.4 degrees Fahrenheit to degrees Celsius has been calculated by applying the formula [°C] = ([°F] − 32) × 5⁄9.The normal core body temperature of a healthy, resting adult human being is stated to be at 98.6 degrees Fahrenheit or 37.0 degrees Celsius. Though the body temperature measured on an individual can vary, a healthy human body can maintain a fairly consistent body temperature that is around the mark of 37.0 degrees Celsius.