What is the surface area of a triangular pyramid if each face has an area of 30 mm2? A. 60 mm2 B. 90 mm2 C. 160 mm2 D. 120 mm2

The number of lateral faces in a pyramid is going to be equal to the number of sides on the base. Since it is a triangular pyramid, there will be 3 lateral faces.

Plus the base, this makes 4 faces.

Each face has an area of 30 mm².

Therefore, the surface area of the pyramid = 4 * 30 = 120 mm²