Capacity of a cylindrical tank — Aptitude Question
Capacity of a cylindrical tank: A cylindrical tank has radius 7 m and height 5 m. What is its capacity in cubic… Answer and worked solution on CodeKairo.
- Topic: Mensuration
- Section: Quantitative Aptitude
- Difficulty: Medium
- Time target: 60 seconds
Question
A cylindrical tank has radius 7 m and height 5 m. What is its capacity in cubic metres? (Take π = 22/7.)
Options
- 550 m³
- 660 m³
- 770 m³
- 880 m³
Show the answer and the worked solution
Correct answer: C. 770 m³
Worked solution
- Volume = (22/7) × 49 × 5 = 22 × 7 × 5 = 770 m³.
Answer: 770 m³.
The idea
Cancel the 7 in π against the radius squared before multiplying. Radii that are multiples of 7 always simplify.
Shortcut. πr² with r = 7 is the stock 154 m² (22 × 7); multiplying by the 5 m height gives 770 m³.
Common trap. "550 m³" — squaring the height instead of the radius: (22/7) × 5² × 7 = 22 × 25 = 550. The volume is πr²h = (22/7) × 7² × 5 = 770 m³.