A outlet pipe can empty a cistern in 8 hours. In what time will it empty 1/2 part of the cistern?

Question: A outlet pipe can empty a cistern in 8 hours. In what time will it empty 1/2 part of the cistern?Solution:The outlet pipe empties one complete cistern in 8 hours.Time taken to empty (1/2) × 8 = 4 hours