Joe wants to build a fence for his dog Charlie.
The lengths of the perimeter of the rectangle that he plans to surround with fence are as follows:
10 feet + 15 feet + 10 feet + 15 +feet.
The total perimeter area of a rectangle is worked out as follows:
10 + 15 + 10 + 15 = 50
Therefore Joe needs 50 feet of fencing to totally surround the rectangle with fence.