How Many Days a Factory Needs to Make 5,000 Polo Shirts?

To find the answer of the above questions you must have following information
  1. SAM of the Polo Shirt (i.e. 16 minutes)
  2. How many machines will be used to make the order (i.e. 20 machines)
  3. Daily working hours (i.e. 8 hours)
  4. Line efficiency (i.e. 100%)

To make 5000 polo shirts-
Capacity required = 5000 X 16 minute = 80,000 minutes = 1333 Hours
Available Capacity/Day = 20 X 8 hours = 160 Hours
Assume that line works at 100% efficiency.

So, Days required (theoretical) to produce 5000 polo shirts = 1333 / 160 = 8.3 days (9 days)
If factory run at 50% efficiency then = 9 X100%/50% = 18 days

For planning add one more day as in practical one day will be lost for loading and line setting.
If you production is calculated at 50% efficiency then you need 19 days to complete the above order.

For further accuracy you can use Learning Curve to calculate day by day production increment up to pick production.

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