Consider the strong electrolytes $Z_m X_n, U_m Y_p$ and $V_m X_n$. Limiting molar conductivity $\left(\Lambda^0\right)$ of $U_m Y_p$ and $\mathrm{V}_{\mathrm{m}} \mathrm{X}_{\mathrm{n}}$ are 250 and $440 \mathrm{~S} \mathrm{~cm}^2 \mathrm{~mol}^{-1}$, respectively. The value of ( $\mathrm{m}+\mathrm{n}+\mathrm{p}$ ) is $\_\_\_\_$ . Given: