In a cubic close packed structure of mixed oxide the lattice is made up of oxide ions, one fifth of tetrahedral voids occupied by divalent $\left(X^{+2}\right)$ions while one half of the octahedral voids are occupied by trivalent ion $\left(Y^{+3}\right)$. The simple formula of the oxide is $X_m{Y}_n{O}_p$. The value of $m+n+p$ is