You are preparing designs for fictional teams with different promises to their users. Read each brief before calculating. A photo archive accumulates bytes over time; an alert service must handle a burst; a reservation service must preserve a business invariant when requests collide.
Use only the supplied inputs. Don't turn an average into a peak without the stated multiplier, and don't treat a percentile as a guarantee for all traffic. You can use the board to record a request path, but the worksheet is checked for the numerical and scope questions. These tasks mix requirements, interview sequencing and units on fresh workloads. Finish by choosing the first failure you would investigate, with a reason that follows from the service's promise.