2201. Amar drew a square. He then erased it and drew a second square whose sides were 3 times the sides of the first square. By what percent was the area of the square increased?
- A. 300%
- B. 400%
- C. 900%
- D. 600%
- E. 800%
Check answer and explanation
Answer: 800%
Explanation Let side of the square = a Area = a 2 ∴ new side = 3a Hence, new area = (3a) 2 =9a 2 Precentage increase in area = a 2 9a 2−a 2 ×100= 800 %