Discussion
What will be increase in area of an equilateral triangle if its side is increased by 20%?
Answer: C
The area of an equilateral triangle is \( \dfrac{\sqrt{3}}{4}a^{2} \), so it varies as the square of the side.
\[ \frac{A'}{A} = \left(\frac{1.2a}{a}\right)^{2} = 1.44 \]
\[ \text{increase} = 1.44 - 1 = 0.44 = 44\% \]
The constant \( \tfrac{\sqrt{3}}{4} \) cancels, so this 44% holds for any shape scaled by 20% - square, circle or triangle alike. The exact rule is \( 2x + \tfrac{x^{2}}{100} = 40 + 4 \).
No comment is present. Be the first to comment.
Loading…
Post your comment
Please log in or register to post a comment.
Examination Categories
- SSC Exams
- Banking Exams
- Teaching Exams
- Civil Services Exams
- Railways Exams
- Engineering Recruitment Exams
- Defence Exams
- State Government Exams
- Police Exams
- Insurance Exams
- Nursing Exams
- Other Government Exams
- NRA CET
- PG Entrance Exams
- Campus Placement
- MBA Entrance Exams
- CUET and UG Entrance
- Judiciary Exams
- Regulatory Body Exams
- Software Development