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1. Around a circular flower bed with a diameter of 16 meters, there is a stone road with a width of 2 meters. What is the area of this stone road? 2. The bottom surface of a wooden basin is round. A 2.552m long iron wire is enclosed at its bottom, and 0.04m is used at the wire joint. What is the diameter of the bottom surface of the basin?
1,3.14*(10*10-8*8)=113.04
2,(2.552-0.04)/3.14=0.8
There is a circular flower bed in the park, with a diameter of 20 meters. There is a 2-meter-wide path around the flower bed. What is the area of the path?
According to the stem analysis, we can get the following conclusions
20 △ 2 = 10 (m), 10 + 2 = 12 (m),
3.14×（122-102），
=3.14×（144-100），
=3.14×44，
=138.16 square meters,
A: the area of this path is 138.16 square meters
A circular flower bed, perimeter is 60 meters, every 6 meters put a pot of orchids, every two pots of orchids placed in the middle of a pot of roses, a total of how many potted flowers?
60÷6×2=20
A circular flower bed has a circumference of 60 meters, and a pot of chrysanthemum is placed every 2 meters around the flower bed. How many pots of chrysanthemum do you need in total?
60 / 2 = 30 pots
This belongs to the problem of planting trees in closed graphs. It's OK to remove the perimeter without adding or subtracting
A round flower bed with a circumference of 27 meters is arranged with a basin of roses every 3 meters around the flower bed, a pot of chrysanthemum is placed between every 2 pots of rose flowers, and several pots of roses and chrysanthemums are placed around the flower bed
Rose = 27 △ 3 = 9 pots
Chrysanthemum = rose = 9 pots
A circular flower bed is planted with a chrysanthemum every 2 meters, a total of 28 plants are planted. How many meters is the perimeter of the flower bed?
28 × 2 = 56 M
Round around the planting of flowers, plant a few plants, there will be a few intervals
The circumference of a circular flower bed is 50.24 meters. In it, 1 / 6 area is reserved for planting rose, and 1 / 4 area is for chrysanthemum. What are the areas of planting rose and chrysanthemum
Diameter: 50.24 / 3.14 = 16 (m) radius: 16 / 2 = 8 (m)
Rose area: 8 * 8 * 3.14 * 1 / 6 = 33.49 (M2)
Chrysanthemum area: 8 * 8 * 3.14 * 4 / 1 = 50.24 (M2)
The circumference of a circular flower bed is 31.4 meters. In the flower bed, 40 percent of the land is planted with roses. How many square meters is the area for planting rose flowers
The diameter of flower bed d = 31.4 / 3.14 = 10m
Area of flower bed s = (10 / 2) ^ 2 * 3.14 = 25 * 3.14 = 78.5 (m ^ 2)
The area of Chinese rose is 78.5 * 40% = 31.4 (m ^ 2)
The circumference of the circular flower bed is 25.12 meters. A quarter of the area is set aside for planting roses. What is the area of planting roses?
25.12/3.14/2=4m
4 * 4 * 3.14 = 50.24 square meters
50.24 / 4 = 12.56 M2
There is a circular flower bed in the park, with a circumference of 31.4 meters. Among them, 1 / 2 species are covered with roses. What is the area of planting roses
Flower bed radius: 31.4 △ 3.14 △ 2 = 5 (m)
Flower bed area: 3.14 × 5 × 5 = 78.5 (M2)
Flower area: 78.5 × 1 / 2 = 39.25 (M2)
RELATED INFORMATIONS
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