The surface area of the rectangular prism would be four times greater. Let’s say you had a rectangular prism with a length of 2, width of 3, and a height of 4. You would do 2( W•L + H•L + H•W) which in this case is 2(3•2 + 4•2 + 4•3) which would get you a surface area of 52.
Now if you were to double the dimensions, the new length would be 4, width would be 6, and the height would be 8. You would also do 2( W•L + H•L + H•W) which in this case is 2( 6•4 + 8•4 + 8•6) which is 208. Therefore, the surface area is 4 times greater.
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