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Zu Chongzhi contrived a more effective method of proceeding than his predecessors had followed,and obtained the accurate value for π.It was 355/113.From this it is seen that China had possessed the accurate value for over 1,300 years before Europe,where the same value was obtained in 1855.
Zu Chongzhi died in 500 at the advanced age of 71.His son Zu hengzhi was another distinguished mathematician following his father.It was he who first derived the world formula about the volume of a spherical ball,which is euqal to 1/6π D3,where D denotes the diameter.