Quiz: Numbers to Know
Five scenario questions with explanations and a visual checkpoint.
Visual checkpoint
Use this diagram to locate the state and failure boundaries tested by the questions. Answer all five questions before revealing feedback; the result is a study checkpoint rather than a certification.
Figure — Arrival rate → Queue backlog (adds work); Queue backlog → Service budget (bounded dispatch); Service budget → Completed work (removes work); Completed work → Retention bytes (stored results); Queue backlog → Deadline check (age vs promise)
Review your reasoning
After checking answers, identify the incorrect assumption behind each missed question. Rewrite it as a rule with a concrete exception or failure case, then return to the lesson.
A queue contains 60,000 jobs, workers finish 500/s, and new work arrives at 300/s. How long to drain?
A queue contains 60,000 jobs, workers finish 500/s, and new work arrives at 300/s. How long to drain?
Your design draft
Clarify assumptions, explain your approach, and test the difficult cases. Save your draft, then compare it with the study notes.
Self-review checklist
Self-guided practice. Automated AI feedback and code execution are not connected.