Topic: Aptitude
What is the maximum area of the rectangle with perimeter $620~mm$?
- A. $24,025~mm^{2}$
- B. $22,725~mm^{2}$
- C. $24,000~mm^{2}$
- D. $24,075~mm^{2}$
Answer: A. $24,025~mm^{2}$
Explanation: A rectangle with a fixed perimeter has its maximum area when it is a square. Perimeter = $4a = 620~mm \implies a = 155~mm$. The maximum area is $155 \times 155 = 24,025~mm^{2}$.