IPA IP 2022 Question 50
A question IPA Japan published in 令和4年度 ITパスポート試験 公開問題 問50, translated into English. ITPEC is based on the same exams.
Software of 120 k steps was developed. When the actual productivity in each process of the development is as shown in the table, how many person-months is the effort for the entire development? Here, productivity is the number of k steps per person-month.
Unit: k steps/person-month
Explanation
50 person-months — each process has to handle all 120 k steps at its own productivity, so compute the effort for each process and add them.
Effort = size ÷ productivity:
- •Design: 120 ÷ 6.0 = 20 person-months
- •Production: 120 ÷ 4.0 = 30 person-months
- •Total: 20 + 30 = 50 person-months
Answer (d)
Why not others:
- •(a) 10 — less than the design process alone needs, 120 ÷ 6.0 = 20 person-months
- •(b) 12 — divides by the summed productivity, 120 ÷ 10 = 12, as though the two processes shared the work instead of each covering all 120 k steps
- •(c) 24 — divides the size once by the average productivity, 120 ÷ 5.0 = 24, counting the 120 k steps for one process instead of for each
Key rule: Productivity is per process: divide the whole size by each process's productivity and add the efforts; never add or average the productivities themselves.
Project Management · AI-written, may contain errors
This question comes from the past questions IPA Japan publishes, translated into English by ITPEC Practice. ITPEC Practice is an independent study tool and is not affiliated with IPA or ITPEC. See the original paper (PDF) or Report an issue.