Kelly is building a cuboid-shaped fish tank with walls that are made of glass. The fish tank will have a plastic rectangular floor with dimensions of 35 cm by 51 cm , and the glass walls will have a height of 26 cm .

Kelly’s fish tank has a plastic floor that is 35 cm by 51 cm, and the glass walls all have a height of 26 cm. Since the floor is plastic, the glass is used only for the four vertical walls. Step 1. Identify the dimensions of the walls.  • Two walls (the “shorter” walls) have a width of 35 cm and a height of 26 cm.  • The other two walls (the “longer” walls) have a length of 51 cm and a height of 26 cm. Step 2. Compute the area of each pair of walls.  • Area of the two 35 cm × 26 cm walls:   Area = 2 × (35 cm × 26 cm) = 2 × 910 cm² = 1820 cm².  • Area of the two 51 cm × 26 cm walls:   Area = 2 × (51 cm × 26 cm) = 2 × 1326 cm² = 2652 cm². Step 3. Find the total area of glass needed:  Total glass area = 1820 cm² + 2652 cm² = 4472 cm². Thus, Kelly will need 4472 cm² of glass for the walls of the fish tank. (Optional additional note: If you ever need to find the volume of the fish tank, it would be 35 cm × 51 cm × 26 cm = 46,410 cm³.)