Perimeter of the equilateral triangle is 15 cm.
Hence, each side of the equilateral triangle = 153=5 cm
Area of the triangular base = √34×(5)2=25√34 cm2
Volume of prism = Base Area×Height=25√345
=125√34 cm3
The base of a prism is an equilateral triangle of perimeter 15 centimetres and its height is 5 centimetres. What is its volume?