The following two reactions are known :

$\begin{array}{l}{\mathrm{Fe}}_2{\mathrm{O}}_{3\left(\mathrm{s}\right)}+3{\mathrm{CO}}_{\left(\mathrm{g}\right)}⟶2{\mathrm{Fe}}_{\left(\mathrm{s}\right)}+3{\mathrm{CO}}_{2\left(\mathrm{g}\right)};\mathrm{\Delta H}=-26.8\mathrm{kJ}\\ {\mathrm{FeO}}_{\left(\mathrm{s}\right)}+{\mathrm{CO}}_{\left(\mathrm{g}\right)}\to {\mathrm{Fe}}_{\left(\mathrm{s}\right)}+{\mathrm{CO}}_{2\left(\mathrm{g}\right)};\mathrm{\Delta H}=-16.5\mathrm{kJ}\end{array}$

The value of $∆$H for the following reaction

${\mathrm{Fe}}_2{\mathrm{O}}_{3\left(\mathrm{s}\right)}+{\mathrm{CO}}_{\left(\mathrm{g}\right)}⟶2{\mathrm{FeO}}_{\left(\mathrm{s}\right)}+{\mathrm{CO}}_{2\left(\mathrm{g}\right)}$ is;