Quadrilateral pyramid a pyramid is called a quadrilateral pyramid if its base is a quadrilateral.

Triangular pyramid a pyramid is called a triangular pyramid if its base is a triangle.

Triangular pyramid a pyramid is called a triangular pyramid if its base is a triangle.

Regular pyramid a pyramid is said to be a regular pyramid if its base is a regular figure.

Regular pyramid a pyramid is said to be a regular pyramid if its base is a regular figure i.e.all sides of its base are equal.

Pyramid of numbers is

Definition a quadrilateral is called a convex quadrilateral if the line containing any side of the quadrilateral has the remaining vertices on the same side of it.

Pyramid of number is

The narrow apex of pyramid is called

The pyramid of number is based on

The age pyramid with broad base indicates