Two shifts in a factory — Caselets Aptitude Question
Two shifts in a factory: A factory runs two shifts. The day shift has 120 workers producing 15 units each; the… Answer and worked solution on CodeKairo.
- Topic: Caselets
- Section: Data Interpretation
- Difficulty: Medium
- Time target: 90 seconds
Question
A factory runs two shifts. The day shift has 120 workers producing 15 units each; the night shift has 80 workers producing 12 units each.
What is the average output per worker across both shifts?
Options
- 13.2
- 13.8
- 14.0
- 14.4
Show the answer and the worked solution
Correct answer: B. 13.8
Worked solution
- Day output = 120 × 15 = 1,800. Night output = 80 × 12 = 960.
- Total = 2,760 units across 200 workers.
- Average = 2,760 ÷ 200 = 13.8.
Answer: 13.8.
The idea
A weighted average, so it leans towards the larger group — here towards 15. Averaging 15 and 12 to get 13.5 ignores the unequal shift sizes.
Shortcut. Shift sizes are 3 : 2, so the average sits 3/5 of the way from 12 to 15: 12 + 1.8 = 13.8.
Common trap. 13.2 — weighting the wrong way (2/5 of the way from 12 to 15), as if the smaller night shift were the larger.