\documentclass[leqno, 12pt]{article}
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\usepackage{amsmath}
\usepackage{multicol}
\usepackage{dcolumn}
\usepackage{fancyhdr}

\newcolumntype{d}[1]{cD{.}{.}{#1}}


\def \HeadingQuestions {\section*{\Large Name: \underline{\hspace{8cm}} \hfill Date: \underline{\hspace{3cm}}} \vspace{-3mm}
{Addition of decimals: Questions} \vspace{1pt}\hrule}

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}
\pagestyle{myfancypagestyle}  % apply myfancypagestyle

% 
\begin{document}
\HeadingQuestions
\vspace{-5mm}
\begin{multicols}{3}
\begin{equation} 
    \raisebox{-0.85cm}{
        \begin{tabular}{d{1.1}}
         &0.8 \tabularnewline
        $+$&5.7 \tabularnewline
        \hline
         & \tabularnewline
        \hline
    \end{tabular}}
\end{equation}



\vspace{-2pt}\begin{equation} 
    \raisebox{-0.85cm}{
        \begin{tabular}{d{1.1}}
         &2.2 \tabularnewline
        $+$&4.6 \tabularnewline
        \hline
         & \tabularnewline
        \hline
    \end{tabular}}
\end{equation}



\vspace{-2pt}\begin{equation} 
    \raisebox{-0.85cm}{
        \begin{tabular}{d{1.1}}
         &4.9 \tabularnewline
        $+$&0.2 \tabularnewline
        \hline
         & \tabularnewline
        \hline
    \end{tabular}}
\end{equation}



\vspace{-2pt}\begin{equation} 
    \raisebox{-0.85cm}{
        \begin{tabular}{d{1.1}}
         &9.7 \tabularnewline
        $+$&0.1 \tabularnewline
        \hline
         & \tabularnewline
        \hline
    \end{tabular}}
\end{equation}



\vspace{-2pt}\begin{equation} 
    \raisebox{-0.85cm}{
        \begin{tabular}{d{1.1}}
         &5.0 \tabularnewline
        $+$&1.7 \tabularnewline
        \hline
         & \tabularnewline
        \hline
    \end{tabular}}
\end{equation}



\vspace{-2pt}\begin{equation} 
    \raisebox{-0.85cm}{
        \begin{tabular}{d{1.1}}
         &7.0 \tabularnewline
        $+$&0.6 \tabularnewline
        \hline
         & \tabularnewline
        \hline
    \end{tabular}}
\end{equation}



\vspace{-2pt}\begin{equation} 
    \raisebox{-0.85cm}{
        \begin{tabular}{d{1.1}}
         &3.1 \tabularnewline
        $+$&2.0 \tabularnewline
        \hline
         & \tabularnewline
        \hline
    \end{tabular}}
\end{equation}



\vspace{-2pt}\begin{equation} 
    \raisebox{-0.85cm}{
        \begin{tabular}{d{1.1}}
         &0.7 \tabularnewline
        $+$&5.2 \tabularnewline
        \hline
         & \tabularnewline
        \hline
    \end{tabular}}
\end{equation}



\vspace{-2pt}\begin{equation} 
    \raisebox{-0.85cm}{
        \begin{tabular}{d{1.1}}
         &8.2 \tabularnewline
        $+$&1.6 \tabularnewline
        \hline
         & \tabularnewline
        \hline
    \end{tabular}}
\end{equation}



\vspace{-2pt}\begin{equation} 
    \raisebox{-0.85cm}{
        \begin{tabular}{d{1.1}}
         &4.2 \tabularnewline
        $+$&5.4 \tabularnewline
        \hline
         & \tabularnewline
        \hline
    \end{tabular}}
\end{equation}



\vspace{-2pt}\begin{equation} 
    \raisebox{-0.85cm}{
        \begin{tabular}{d{1.1}}
         &2.4 \tabularnewline
        $+$&4.3 \tabularnewline
        \hline
         & \tabularnewline
        \hline
    \end{tabular}}
\end{equation}



\vspace{-2pt}\begin{equation} 
    \raisebox{-0.85cm}{
        \begin{tabular}{d{1.1}}
         &5.6 \tabularnewline
        $+$&1.2 \tabularnewline
        \hline
         & \tabularnewline
        \hline
    \end{tabular}}
\end{equation}



\vspace{-2pt}\begin{equation} 
    \raisebox{-0.85cm}{
        \begin{tabular}{d{1.1}}
         &2.4 \tabularnewline
        $+$&0.9 \tabularnewline
        \hline
         & \tabularnewline
        \hline
    \end{tabular}}
\end{equation}



\vspace{-2pt}\begin{equation} 
    \raisebox{-0.85cm}{
        \begin{tabular}{d{1.1}}
         &7.0 \tabularnewline
        $+$&1.9 \tabularnewline
        \hline
         & \tabularnewline
        \hline
    \end{tabular}}
\end{equation}



\vspace{-2pt}\begin{equation} 
    \raisebox{-0.85cm}{
        \begin{tabular}{d{1.1}}
         &1.9 \tabularnewline
        $+$&7.5 \tabularnewline
        \hline
         & \tabularnewline
        \hline
    \end{tabular}}
\end{equation}



\vspace{-2pt}\begin{equation} 
    \raisebox{-0.85cm}{
        \begin{tabular}{d{1.1}}
         &3.1 \tabularnewline
        $+$&2.5 \tabularnewline
        \hline
         & \tabularnewline
        \hline
    \end{tabular}}
\end{equation}



\vspace{-2pt}\begin{equation} 
    \raisebox{-0.85cm}{
        \begin{tabular}{d{1.1}}
         &0.6 \tabularnewline
        $+$&6.7 \tabularnewline
        \hline
         & \tabularnewline
        \hline
    \end{tabular}}
\end{equation}



\vspace{-2pt}\begin{equation} 
    \raisebox{-0.85cm}{
        \begin{tabular}{d{1.1}}
         &8.3 \tabularnewline
        $+$&0.3 \tabularnewline
        \hline
         & \tabularnewline
        \hline
    \end{tabular}}
\end{equation}



\vspace{-2pt}\begin{equation} 
    \raisebox{-0.85cm}{
        \begin{tabular}{d{1.1}}
         &4.2 \tabularnewline
        $+$&0.3 \tabularnewline
        \hline
         & \tabularnewline
        \hline
    \end{tabular}}
\end{equation}



\vspace{-2pt}\begin{equation} 
    \raisebox{-0.85cm}{
        \begin{tabular}{d{1.1}}
         &0.5 \tabularnewline
        $+$&9.3 \tabularnewline
        \hline
         & \tabularnewline
        \hline
    \end{tabular}}
\end{equation}



\vspace{-2pt}\begin{equation} 
    \raisebox{-0.85cm}{
        \begin{tabular}{d{1.1}}
         &5.2 \tabularnewline
        $+$&0.3 \tabularnewline
        \hline
         & \tabularnewline
        \hline
    \end{tabular}}
\end{equation}



\vspace{-2pt}\begin{equation} 
    \raisebox{-0.85cm}{
        \begin{tabular}{d{1.1}}
         &0.4 \tabularnewline
        $+$&6.8 \tabularnewline
        \hline
         & \tabularnewline
        \hline
    \end{tabular}}
\end{equation}



\vspace{-2pt}\begin{equation} 
    \raisebox{-0.85cm}{
        \begin{tabular}{d{1.1}}
         &5.4 \tabularnewline
        $+$&0.4 \tabularnewline
        \hline
         & \tabularnewline
        \hline
    \end{tabular}}
\end{equation}



\vspace{-2pt}\begin{equation} 
    \raisebox{-0.85cm}{
        \begin{tabular}{d{1.1}}
         &0.6 \tabularnewline
        $+$&1.2 \tabularnewline
        \hline
         & \tabularnewline
        \hline
    \end{tabular}}
\end{equation}



\vspace{-2pt}\begin{equation} 
    \raisebox{-0.85cm}{
        \begin{tabular}{d{1.1}}
         &4.2 \tabularnewline
        $+$&3.6 \tabularnewline
        \hline
         & \tabularnewline
        \hline
    \end{tabular}}
\end{equation}



\vspace{-2pt}
\end{multicols}
\end{document}
