A square that is 6ft on a side is placed inside a rectangle that has a width of 10ft and a length of 18ft. What is the area of the region inside the rectangle that surrounds the square?

To find the area of the region inside the rectangle that surrounds the square, we need to find the area of the rectangle and subtract the area of the square.

1. Area of the rectangle:
Given length = 18ft, width = 10ft
Area of the rectangle = length x width
Area = 18 \times 10 = 180 \, ft^2

2. Area of the square:
Given side length = 6ft
Area of the square = side length x side length
Area = 6 \times 6 = 36 \, ft^2

3. Area of the region inside the rectangle that surrounds the square:
Area = Area of rectangle - Area of square
Area = 180 - 36 = 144 \, ft^2

\boxed{144 \, ft^2} is the area of the region inside the rectangle that surrounds the square.