Final answer:
The surface area of the open-top box is 408 cm².
Step-by-step explanation:
To find the surface area of an open-top box, we need to calculate the area of all its faces and add them together.
For the open-top box with a length of 9 cm, width of 6 cm, and height of 10 cm, we have:
Top face area: length x width = 9 cm x 6 cm = 54 cm²
Bottom face area: same as top face = 54 cm²
Two side face areas: height x width = 10 cm x 6 cm = 60 cm² x 2 = 120 cm²
Front and back face areas: length x height = 9 cm x 10 cm = 90 cm² x 2 = 180 cm²
Adding all these areas together, we get:
Total surface area = top face area + bottom face area + two side face areas + front and back face areas = 54 cm² + 54 cm² + 120 cm² + 180 cm² = 408 cm².