More Questions from Area

The length of a rectangle is reduced by 20% and breadth is kept constant, and the new figure that is formed is a square. Consider the following statements: 1. The area of square is 25% less than the area of rectangle. 2. The perimeter of square is approximately 11% less than the perimeter of rectangle. 3. The diagonal of square is approximately 12% less than the diagonal of rectangle. Which of the statements given above is/are correct?

Aptitude Area Difficulty: Hard
Choose an option
  • A
    1 only
  • B
    1 and 2
  • C
    2 and 3
  • D
    1, 2 and 3

Answer

Correct Answer: 2 and 3

Explanation

### Concept & Shape Geometry Analysis Compare derived dimensions of modified shapes by setting the new dimensions equal to establish the base ratio. $$ Ratio = \frac{New - Old}{Old} \times 100 $$ ### Step-by-Step Solution * Initial parameters and variable relationships between the rectangle and square are established. * Standard geometric formulas for area, perimeter, and diagonal are evaluated and compared. * Final evaluation confirms Statements 2 and 3 perfectly match the computed variance. ### Exam Strategy & Shortcut Assume $B = 8$, making initial $L = 10$. Original perimeter = 36, Square perimeter = 32. The drop is $4/36 = 11.11\%$. Skip calculating the area since option elimination heavily favors checking the perimeter first. ### Common Pitfall Assuming length and breadth can be arbitrary numbers without establishing their rigid mathematical relationship dictated by the square formation constraint. ### Final Answer Therefore, the correct answer is **2 and 3**.
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