Why a hexagonal close-packed structure and a cubic close-packed structure for a given element would be expected to have the same density?

Hexagonal closest packed structure and cubic closest packed structure for a given element would be expected to have the same density because of

In a closed packed structure

What is the co-ordination number of each sphere in (i) Hexagonal close packed structure. (ii) Cubic close packed structure. (iii) Body centred cubic packed structure.

What is the co-ordination number of each sphere in (i) Hexagonal close packed structure. (ii) Cubic close packed structure. (iii) Body centred cubic packed structure.

Hexagonal closely packed| Cubicaly closely packed

In a cubic close packed structure the number of nearest neighbours for a given lattice point is

In a cubic close packed structure the number of nearest neighbours for a given lattice point is

Define: (i) Cubic close-packed structure (ii) Hexagonal close-packed structure (iii) Non-stoichiometric defect.