First, we assume 100 trucks (or 100 predictions), as the percentages are easiest to scale on a base of 100.
Using the confusion matrix:
True Positives (Predicted Fail & Actually Fails): 80 trucks — correct → +1 hr each = +80 hrs
False Positives (Predicted Fail & Actually Succeeds): 20 trucks — incorrect → –4 hrs each = –80 hrs
False Negatives (Predicted Succeed & Actually Fails): 15 trucks — incorrect → –4 hrs each = –60 hrs
True Negatives (Predicted Succeed & Actually Succeeds): 85 trucks — correct → +1 hr each = +85 hrs
Now calculate net hours:
Total gain: 80 hrs (TP) + 85 hrs (TN) = +165 hrs
Total loss: 80 hrs (FP) + 60 hrs (FN) = –140 hrs
Net Impact: 165 – 140 = +25 hours saved
So the correct answer is:
Answer: B (25 hours saved)
However, based on the table provided (which appears to be normalized as percentages), the values apply to a total of 100 predictions. Let's recalculate carefully and validate.
Breakdown:
TP = 80% → 80 × +1 hr = +80 hrs
FP = 20% → 20 × –4 hrs = –80 hrs
FN = 15% → 15 × –4 hrs = –60 hrs
TN = 85% → 85 × +1 hr = +85 hrs
Total hours = +80 + 85 – 80 – 60 = +25 hrs
Final Answer: B. 25 hours saved
Official References:
CompTIA DataX (DY0-001) Study Guide – Section 4.3:“Business cost/benefit analysis based on confusion matrix performance is critical for evaluating model ROI.”