Hope primary school has a rectangular flower bed. When it was built, the length and width of the flower bed were increased by 3 meters, and the area of the flower bed was increased by 60 square meters______ Rice

Hope primary school has a rectangular flower bed. When it was built, the length and width of the flower bed were increased by 3 meters, and the area of the flower bed was increased by 60 square meters______ Rice

As shown in the figure: A is the original rectangle, B + C + D is the increased part after expansion, d = 3 × 3 = 9 (square meters), B = 3 × width, C = 3 × length, so B + C + D = 3 × width + 3 × length + 9 = 60, 3 × (width + length) = 60-9, width + length = 51 △ 3, width + length = 17; so perimeter = (width + length) × 2, = 17 × 2, = 34 (meters); answer: the original perimeter is 34 meters, so the answer is: 34

A rectangular flower bed, 400 meters in circumference, the ratio of length and width is 3:2, how many square meters is the area of this flower bed?

The length is 400 ／ 2 ／ (3 + 2) X3 = 120
The width is 400 ／ 2 ／ (3 + 2) x2 = 80
The area is 120x80 = 9600 square meters

The school has a rectangular flower bed, 8 meters long. When the campus is built, the length of the flower bed is increased by 3 meters, so the area of the flower bed is increased by 18 square meters
It's perimeter!

Assuming that the width of the flower bed is x, the former area is 8x, but now the length is increased by 3, that is, 11, and the area becomes 11x, so 11x-8x = 18, that is, x = 6. Then the width is 6. In the past, the perimeter of the flower bed was 28, and after the change, the bottom area was 34