The base of a prism is in the shape of an equilateral triangle. If the perimeter of the base is 18 cm and the height of the prism is 20 cm, then what is the volume (in cm3) of the prism?
Show answer & explanation
Correct answer: D
Explanation
The correct answer is option 4 i.e. 180√3
Base of prism is an equilateral triangle
Perimeter = 18 cm
Let side = a
3a = 18
a = 6
height of prism = 20 cm
Area of base = √3/4 × 6 × 6 = 9√3 cm2
Volume of prism = 9√3 × 20 = 180√3 cm3