The least amount of wrapping paper that Amy needs to wrap the present is 1936in².
Surface area is simply the amount of space covering the outside of a 3-dimensional object.
The surface area of a rectangular prism is expressed;
A = 2( wl + hl + hw )
Given the data in the question;
To determine the least amount of wrapping paper that Amy needs to wrap the present in the shape of a rectangular prism, we substitute our given values into the expression above.
A = 2( wl + hl + hw )
A = 2( (16in×20in) + (18in×20in) + (18in×16in) )
A = 2( 320in² + 360in² + 288in² )
A = 2( 968in² )
A = 1936in²
Therefore, the least amount of wrapping paper that Amy needs to wrap the present is 1936in².
Learn more about the surface area of a rectangular prism here: https://brainly.com/question/14987814
