The courtyard outside East Middle School is in the shape of a rectangle and half-circle.

What is the approximate area of the courtyard? (100m and 50 m)

A. 8,925 m2
B. 6,963 m2
C. 5,982 m2
D. 5,079 m2

1 answer

To find the area of the courtyard that is in the shape of a rectangle and a half-circle, we can break it down into two parts: the rectangular area and the area of the half-circle.

  1. Calculate the area of the rectangle: The formula for the area of a rectangle is: \[ \text{Area of rectangle} = \text{length} \times \text{width} \] Given dimensions:

    • Length = 100 m
    • Width = 50 m

    \[ \text{Area of rectangle} = 100 , \text{m} \times 50 , \text{m} = 5000 , \text{m}^2 \]

  2. Calculate the area of the half-circle: The formula for the area of a circle is: \[ \text{Area of circle} = \pi r^2 \] Since we have a half-circle, we need to divide this area by 2. The radius of the half-circle is half the width of the rectangle, which is: \[ r = \frac{50 , \text{m}}{2} = 25 , \text{m} \]

    So, the area of the half-circle is: \[ \text{Area of half-circle} = \frac{1}{2} \pi r^2 = \frac{1}{2} \pi (25 , \text{m})^2 \] \[ = \frac{1}{2} \pi (625 , \text{m}^2) \approx \frac{1}{2} \times 3.14 \times 625 \approx 981.25 , \text{m}^2 \]

  3. Total area of the courtyard: Now, we add both areas together: \[ \text{Total Area} = \text{Area of rectangle} + \text{Area of half-circle} \] \[ \text{Total Area} = 5000 , \text{m}^2 + 981.25 , \text{m}^2 \approx 5981.25 , \text{m}^2 \]

Rounding this value gives approximately \( 5982 , \text{m}^2 \).

Based on the options provided, the closest answer would be: C. 5,982 m²