There is a circular flower bed with a diameter of 16m, and a 2m wide path is built around it (1) What is the area of this path? (2) How many lamps should be installed along the edge of the circular path every 5m?

(1) 16 △ 2 = 8 (m), 8 + 2 = 10 (m),
3×（102-82），
=3×（100-64），
=3×36，
=108 square meters;
A: the area of this path is 108 square meters
（2）3×10×2÷5，
=60÷5，
=12;
A: a total of 12 lamps will be installed

The Urban Construction Bureau has built a stone path with a width of 2 meters around a circular fountain with a diameter of 16 meters. Please calculate the area of this road? (students can draw pictures first, which can make it easier to solve problems)

As shown in the figure:
16 △ 2 = 8 (m),
8 + 2 = 10 (m)
So the area of the path is:
3.14×（102-82）
=3.14×（100-64）
=3.14×36
=113.04 (M2)
A: the area of the path is 113.04 square meters

There is a round flower bed in the park, with a diameter of 18 meters. There is a 1-meter pipe path around him. 1: the area of the stone road. 2. A lamp every 0.4 meters along the ring road

1. Area of gravel road 3.14 * (19 / 2 * 19 / 2-18 / 2 * 18 / 2)
2、3.14*19/0.4

Build a 1-meter wide stone road around a pool with a diameter of 8 meters. What is the area of this stone road?

The radius of the inner circle is:
8 △ 2 = 4 (m);
3.14×[（4+1）2-42]
=3.14×[25-16]
=3.14×9
=28.26 (square meters)
Answer: the area of Shizi road is 28.26 square meters

The park has a circular flower bed with a diameter of 18 meters. A 1-meter-wide circular stone road is built around it. What is the area of this stone road?

Firstly, calculate the area of the circular stone path: 18 ﹣ 2 = 9 (m) 9 + 1 = 10 (m) 10? 2 × 3.14 = 314 (M? 2); then calculate the area of the circular flower bed: 9 ﹣ 3.14 = 254.34 (M? 2); finally, subtract the area of the circular flower bed from the total area: 314-254.34 = 59.66 (M m2)

To build a 1-meter-wide path around a circular flower bed with a diameter of 12 meters, the middle road covers an area of______ Square meters

3.14×（12
2+1）2-3.14×（12
2）2，
=3.14×72-3.14×62，
=3.14×49-3.14×36，
=153.86-113.04，
=40.82 (M2);
Answer: this path covers an area of 40.82 square meters
So the answer is: 40.82

A circular stone road with a width of 2 meters is paved outside the circular flower bed with a diameter of 8 meters. What is the area of this stone road?

D=8
So r = 4
Therefore, flower bed + pavement circle r = 4 + 2 = 6
So S-ring = π (r? - R) = π * 20 = 20 π

Lay a 2-meter wide road around a 10 meter diameter circular garden

10 △ 2 = 5 (m),
5 + 2 = 7 (m),
3.14×（72-52），
=3.14×（49-25），
=3.14×24，
=75.36 square meters,
A: the area of this path is 75.36 square meters

A 1-meter wide stone road is paved around the 31 kilometer flower bed. The area of the stone road is () square meters

The area of the gravel road = [(31000 / 2 π) + 1] 2 π - (31000 / 2 π) π
=4937,3²π-4936,3²π
=24376931,3π-24367057,7π
=9873,6π
=31003,1 (M2)

A 1-meter wide stone road is paved around the circular flower bed with a circumference of 37.68 meters. How many square meters does the stone road cover?

Equivalent to the area of the circle, the perimeter of the flower bed is 37.36, and the radius is 6 meters; the radius of the outer ring is 6 + 1 = 7 meters, so the area of the circle is pi * 49 - pi * 36 = 13 * pi = 40.82 square meters

There is a circular flower bed with a diameter of 16m, and a 2m wide path is built around it (1) What is the area of this path? (2) How many lamps should be installed along the edge of the circular path every 5m?