Nina glues pictures on a rectangular piece of cardboard.
The piece of cardboard is 20 inches long and 9 inches wide.
Each rectangular picture is 7 inches long and 4 inches wide.
She glues 3 pictures on the cardboard. The pictures do not overlap.
What is the area of the cardboard that is not covered by pictures? _ square inches
First, let's calculate the total area of the cardboard:
Length x Width = 20 inches x 9 inches = 180 square inches
Next, let's calculate the area covered by the pictures:
Each picture has an area of 7 inches x 4 inches = 28 square inches
Since Nina glues 3 pictures on the cardboard, the total area covered by pictures is 3 pictures x 28 square inches = 84 square inches
Finally, to find the area of the cardboard that is not covered by the pictures, we subtract the area covered by the pictures from the total area of the cardboard:
180 square inches - 84 square inches = 96 square inches
Therefore, the area of the cardboard that is not covered by pictures is 96 square inches.