The perimeter of the circle can be calculated using the following formula: [img alt_text = 'Circle perimeter' description = ''] https:///wp-content/uploads/2017/03/kor-K.jpg [/ img ] That is, if we know the radius of the circle, which is, for example, 10 cm, and we know that the value of pi is 3.14, then K = 2x10x3.14, that is, K = 62.8 cm.