The total length did Carlos swim is 420 feet.
To find the perimeter.
What is rectangle?
A rectangle is a type of quadrilateral that has its parallel sides equal to each other and all the four vertices are equal to 90 degrees.
Given that:
Let the perimeter of rectangular swimming pool be x metres.
Then, its length =21 feet.
The width of the pool = 9 feet
The Perimeter of a rectangle =2(Length+Breadth)
According to the given condition, we have
Perimeter of a rectangle =2(Length+Breadth)
Perimeter of a rectangle=2(21+9)
Perimeter of a rectangle=2*30
Perimeter of a rectangle=60 feet
But, carlos swam the perimeter of a rectangular pool seven times.
Old perimeter=7*60=420 feet
Thus ,the total length did Carlos swim is 420 feet.
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