Average monthly output — Tables & Charts Aptitude Question
Average monthly output: | Month | Unit A | Unit B | Unit C | |-----------|--------|--------|--------| | January |… Answer and worked solution on CodeKairo.
- Topic: Tables & Charts
- Section: Data Interpretation
- Difficulty: Medium
- Time target: 60 seconds
Question
| Month | Unit A | Unit B | Unit C |
|---|---|---|---|
| January | 400 | 300 | 500 |
| February | 450 | 350 | 400 |
| March | 500 | 400 | 600 |
| April | 550 | 450 | 450 |
What was the average monthly production of Unit C?
Options
- 475
- 487.5
- 500
- 512.5
Show the answer and the worked solution
Correct answer: B. 487.5
Worked solution
- Unit C total = 500 + 400 + 600 + 450 = 1,950.
- Average = 1,950 ÷ 4 = 487.5.
Answer: 487.5.
The idea
A non-integer average is perfectly normal. Rounding to a whole number would land on a distractor.
Shortcut. Work from 500: the deviations 0, −100, +100, −50 sum to −50, and −50 ÷ 4 = −12.5, giving 487.5.
Common trap. 500 — seeing +100 and −100 cancel and taking 500 as the average, forgetting that April's 450 pulls it down by 12.5.