A rectangle is 50 meters long, its width is the diameter of a circle, and its circumference is 200-50 * 2 = 100. This is the inner ring, the diameter is = 100/3. 14.

For the excircle, the diameter = 100/3. 14+8.

therefore

(1) Playground area = 50× (100/3.14+8)+1/4× 3.14× (100/3.

(2) Lawn area = 50× (100/3.14)+1/4× 3.14 × (100/3.14.

(3) Runway area = playground area-lawn area

2:

The previous answer is also correct.

150×( 100÷3. 14+4×2)+3. 14×( 100÷3. 14÷2+4)^2

2[50×( 100÷3. 14)+3. 14×( 100÷3. 14÷2)^2]×80

3 Runway area = playground area-lawn area

3:

Solution: The length of a rectangle is 50 meters, and the width is the diameter of a circle. The circumference of a circle is 200-50x2 =100m, and the inner circle is 100/3. 14.

External circle: diameter = 100/3. 14+8.

So:

(1) Playground area: 50× (100/3.14+8)+3.14× radius (100/3.14+)

(2) Lawn area: 50× (100/3.14)+3.14× radius (100/3. 14)/2, and then multiply the sum by 80.

(3) The runway area is the playground area-lawn area.

4:

The answer to this question is changeable, not unique.

Because the 200-meter-long track inside is composed of two straight lines (straight lines) and two curved lines (curved lines), the length of the straight lines and the radius of the curved lines can be changed, and many specifications can be found in professional sports books. Just ask the PE teacher.

5:

Solution:

(1) playground area: 50× (100/3.14+8)+3.14× radius (100/3.14+)

(2) Lawn area: 50× (100/3.14)+3.14× radius (100/3. 14)/2, and then multiply the sum by 80.

(3) The runway area is the playground area-lawn area.