What is the formula of a compound in which the element Y forms ccp lattice and atoms of X occupy `2//3^(rd)` of tetrahedral voids ?

Explanation

The number of tetrahderal voids formed is equal to twice the number of atoms of element B and only `(2)/(3)`rd of these are occupied by the atoms of element A. Hence the ratio of the number of atoms of A and B is `2xx(2//3) : 1 or 4 : 3` and the formula of the compound is `A_(4)B_(3).`