A rectangle has integer length sides and an area of . What is the least possible perimeter of the rectangle?
Pick one
Solution
Note that . A rectangle will have perimeter . It is straightforward to check the other possible dimensions to show that this gives the rectangle with the least possible perimeter:
* gives a perimeter of .
* gives a perimeter of .
* gives a perimeter of .
* If one of the dimensions is , , , or , then the other dimension is greater than , yielding rectangles with greater perimeters.
Thus the least possible perimeter is .
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