ITPEC FE Subject A October 2025 Question 38

Defect Correction Cost Estimation — calculate expected correction cost using defect rates and classification.

Given conditions:
- Program size: 2,000 k steps
- Defect rate: 0.04 defects / k steps
- Annual discovery rate: 20%
- Classification: major 20%, minor 80%
- Cost: major $20,000, minor $5,000
- First year: only major defects corrected

Step-by-step:
- Total potential defects: 2,000 × 0.04 = 80
- Discovered in year 1: 80 × 0.20 = 16
- Major impact defects: 16 × 0.20 = 3.2
- Correction cost: 3.2 × 20,000 = 64,000

Why not others:
- (b) 128,000 — includes minor defect costs, but condition (6) limits to major only
- (c) 160,000 — ignores the 20% annual discovery rate
- (d) 640,000 — ignores both discovery rate and major-only filter

Key rule: Apply filters sequentially: total defects → discovery rate → classification → cost. Read conditions carefully for scope limitations (e.g., "only major impact").

AI-generated — may contain errors