A product must be ground polished weighed and inspected The

A product must be ground, polished, weighed and inspected. The grinding must precede the polishing and the weighting and the polishing must precede the inspection. Grinding takes 7 units of time, polishing takes 10 units of time, weighting takes 1 unit of time for an unpolished product and 3 units of time for a polished one, and inspection takes 2 units of time for an unweighed product and 3 units of time for a weighed one. What is the fastest production schedule?

Solution

Schedule 1 is the fastest

Schedule 1	7 units	1 units	10 min	3 units	21 units
	Grinding	Weighing	Polishing	Inspection	Total
Schedule 2	7 units	10 units	2 units	3 units	22 units
	Grinding	Polishing	Inspection	Weighing	Total