Total surface area of prism = Curved surface area + 2 × Area of base ⇒ 608 = Perimeter of base × height + 2 × Area of base ⇒ 608=4x×15+2x2 (When x = side of square) ⇒ x2+30X−304=0 ⇒ x2+38x−8x−304=0 ⇒ x(x+38)−8(x+38)=0 ⇒ (x−8)(x+38)=0⇒x=8 Volume of prism = Area of base x height 8×8×15=960cm3