We conclude that the width of the rectangular garden is 80 feet.
Let's define the variables:
The perimeter of a rectangle of length L and width W is given by the simple formula:
P = 2*(L + W)
The perimeter is equal to 400ft, then:
400ft = 2*(L + W)
And we know that the length is 120ft, then:
L = 120ft.
Replacing the length in the perimeter equation we get:
400ft = 2*(120ft + W)
Now we can solve this linear equation for W.
400ft/2 = 120ft + W
200ft = 120ft + W
200ft - 120ft = W
80ft = W
We conclude that the width of the rectangular garden is 80 feet.
If you want to learn more about rectangles:
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