k+263.48=381.09
$${\mathtt{k}}{\mathtt{\,\small\textbf+\,}}{\mathtt{263.48}} = {\mathtt{381.09}} \Rightarrow {\mathtt{k}} = {\frac{{\mathtt{11\,761}}}{{\mathtt{100}}}} \Rightarrow {\mathtt{k}} = {\mathtt{117.61}}$$