Question

1. In the tetrahedron, three triangles meet at each vertex. What is the sum of the interior angles? Is it less than 360 degrees?

Answer 1

Answer:

Simplest Reason: Angles at a Vertex

it must be less than 360 degrees. Because at 360° the shape flattens out! A regular triangle has internal angles of 60°, so we can have: 3 triangles (3×60°=180°) meet