The average length of the sides of triangle ABC is 12. What is the perimeter of triangle ABC?  Choose the most appropriate option: A) 4 B) 6 C) 12 D) 24 E) 36

Rationale: ( average ) = ( perimeter ) / 3 ; 12 = ( perimeter ) / 3 ; ( perimeter ) = 36 . answer : e .
Answer: E