Line balancing and scheduling problems are worked out to balance production line.

Two ways to balance a multi-product line

1) balance the line for each product and product batches for inventory  high volume of inventory.

2) balance the line for all products by using average processing times.

it is difficult to balance a line for all products : scheduling different products must be considered.
Balancing & Scheduling : as two separate but related problems.

Even in the case where the problems can be solved optimally, the optimality of the overall  solution may not be obtained by solving problem separately.

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Assembly line balancing