To find which container would use the least amount of wrapping paper, we need to find the surface area for each container.
The first container represents the figure of a triangular prism.
The formula for the surface is if given by:
The base area of the two triangles bases:
Then:
The perimeter of the base:
= 7cm + 7 cm+10cm
=24 cm
The length of the prism = 30 cm
Replacing these values on the surface area formula:
Then, the surface area for the triangular prism is:
SA = 770 cm²
Now, the second figure presents a rectangular prism.
Where the surface area is given by :
In this case:
Lenght = 30cm
Height =10cm
Breath = 5cm
Replacing on the formula:
Then:
SA = 1000cm²
Hence, the first figure which represents the triangular prism will allow Tanika to use the least amount of wrapping paper.