A document is to be typed, and signed. Typing takes 2 hours, proofreading 1 hour, and singing 30 minutes. If only one task can be done at a time, what is the minimum time required to complete all three tasks for three documents, if tasks can be parallelized across different staff?
Answer: 4.5 Hours
Explanation
With parallelization across different staff, the tasks can be efficiently pipelined.
Given the schedule:
1. Typist takes 2 hours per document.
2. Proofreader takes 1 hour per document.
3. Signer takes 0.5 hours per document.
The pipeline schedule shows:
After Doc 1 is typed (2 hours), it moves to proofreading, and Doc 2 starts typing.
By the time Doc 3 is done typing (6 hours total for typing 3 documents), Doc 1 would have been signed (3.5 hours total for Doc 1 to be signed after starting typing).
The critical path here is determined by the longest sequence in the pipeline, which is typing (6 hours for 3 documents).
Given the pipelined schedule provided:
The last document (Doc 3) finishes signing at 4.5 hours.
