Answer:
The shape of each cut surface is a rectangle. The dimensions of the first cut surface are 8 inches by 10 inches, and the dimensions of the second cut surface are 10 inches by 20 inches.
The area of the first cut surface is 8 inches x 10 inches = 80 square inches. The area of the second cut surface is 10 inches x 20 inches = 200 square inches.
To find the total area Jenny needs to paint, we need to add the area of the first cut surface to the area of the second cut surface.
Total area = Area of first cut surface + Area of second cut surface
Total area = 80 square inches + 200 square inches
Total area = 280 square inches
Therefore, Jenny needs to paint a total area of 280 square inches.