Base from area and height — Mensuration Aptitude Question
Base from area and height: A triangle has an area of 84 cm² and a height of 12 cm. What is its base? Answer and worked solution on CodeKairo.
- Topic: Mensuration
- Section: Quantitative Aptitude
- Difficulty: Easy
- Time target: 45 seconds
Question
A triangle has an area of 84 cm² and a height of 12 cm. What is its base?
Options
- 7 cm
- 12 cm
- 14 cm
- 21 cm
Show the answer and the worked solution
Correct answer: C. 14 cm
Worked solution
- 84 = ½ × b × 12 = 6b.
- b = 14 cm.
Answer: 14 cm.
The idea
Rearrange the area formula for whichever quantity is missing. Forgetting the half gives 7, which is offered.
Shortcut. Base = 2 × area ÷ height = 168 ÷ 12 = 14 cm.
Common trap. "7 cm" — dividing 84 by 12 and forgetting the ½ in the area formula.