The surface area of the composite figure is 510 square centimeters.
Let's say it's a rectangular prism with dimensions 3cm x 10cm x 15cm.
The surface area of a rectangular prism can be calculated using the formula:
Surface Area = 2lw + 2lh + 2wh
Where:
l = length
w = width
h = height
Given:
l = 15cm
w = 10cm
h = 3cm
Surface Area = 2 * (15 * 10) + 2 * (15 * 3) + 2 * (10 * 3)
Surface Area = 2 * 150 + 2 * 45 + 2 * 30
Surface Area = 300 + 90 + 60
Surface Area = 450 + 60
Surface Area = 510 square centimeters
Therefore, the surface area of the composite figure is 510 square centimeters.