Savol 1

$\begin{array}{cc}& \begin{array}{cc}\mathrm{<mn>1</mn>}& \mathrm{<mn>8</mn>}\end{array}\\ \underline{\times }& \underline{\begin{array}{cc}& \mathrm{<mn>3</mn>}\end{array}}\\ & \begin{array}{cc}\mathrm{<mn>5</mn>}& \mathrm{<mn>4</mn>}\end{array}\end{array}$