Question

15. The base of a prism

ters
base of a prism is an equilateral trian
with an area of 73.2 square centimete
the area of each lateral face is 104 squar
eters. Riley incorrectly claims that the
surface area is 250.4 square centimeters.
centimeters. Riley incorre
a. What is the correct surface area?
b. What could have been Riley's error?​

Answer 1

Part a)
`SA=458.4\ cm^2`

Part b) Added only one side triangular face instead of three side triangular faces

Explanation:

we know that

The surface area of a triangular prism is equal to two times the area of the base plus the area of its three triangular faces

so

`SA=2(73.2)+3(104)`

`SA=146.4+312`

`SA=458.4\ cm^2`

Riley's error was

`SA=2(73.2)+(104)=250.4\ cm^2`

added only one side triangular face instead of three side triangular faces