Question

The length of a rectangle is $\frac{2}{5}$ of the radius of a circle. The radius of the circle is equal to the side of a square whose area is 4900 m². What is the area (in m²) of the rectangle, if its breadth is 20 m?

• A. 960
• B. 400
• C. 560
• D. 1400

Answer 1

Answer:

C. 560

Solution:

Given:

The breadth of the rectangle = 20 m

Length of the rectangle $=\frac{2}{5}$ × Radius of the circle

The radius of the circle is equal to the side of the square

Area of the square = 4900 m²

Formula Used:

1. Area of a square = (Side)²

2. Area of a rectangle = Length × Breadth

Calculation:

Side of the square = √4900 = 70 m

The radius of the circle = 70 m

Length of the rectangle = 2525 × 70 = 28 m

Area of the rectangle = 28 × 20 = 560 m²

∴ The area of the rectangle is 560 m².