\documentclass[a4paper]{article}

\usepackage[utf8x]{inputenc}
\usepackage[T1]{fontenc}
\usepackage{amsmath, amssymb}


\usepackage[francais,bloc,completemulti]{automultiplechoice}
\usepackage[french]{babel}

\NewEnviron{qcm}[1]{%
  \def\arg{#1}%
  \expandafter\element\expandafter\arg\expandafter{\BODY\par}}

\makeatletter
\renewcommand{\element}[2]{%
  \AMC@prepare@element{#1}%
  \global\csname #1@\romannumeral\AMCtok@k\endcsname={#2}%
}
\makeatother

\def\AMCdecimalPoint{\raisebox{1ex}{\bf ,}}

\usepackage{multicol}

\begin{document}

%%% préparation des groupes

\setdefaultgroupmode{withreplacement}


\begin{qcm}{produit-scalaire}
	\begin{questionmultx}{A}

		\[ \frac{2}{3} \]
		\def\AMCntextVHead#1{%
			\edef\col{#1}
			\edef\head{%$
				\if\col0c\fi
				\if\col1d\fi
				\if\col2U\fi
				\if\col3D\fi
			}\emph{\head}}
		\begin{center}
			\emph{Arrondir la réponse si besoin.}\\
			\AMCnumericChoices{2/3}{digits=3,decimals=2,sign=false,
				borderwidth=0pt,backgroundcol=lightgray,approx=1, vertical=true, 
				vhead=true, scoreapprox=1
			}
		\end{center}
	\end{questionmultx}
\end{qcm}

\begin{qcm}{produit-scalaire}
	\begin{questionmultx}{B}
		
		\[ \frac{9}{4} \]
		\def\AMCntextVHead#1{%
			\edef\col{#1}
			\edef\head{%$
				\if\col0d\fi
				\if\col1U\fi
				\if\col2D\fi
				\if\col3C\fi
			}\emph{\head}}
		\begin{center}
			\emph{Arrondir la réponse si besoin.}\\
			\AMCnumericChoices{9/4}{digits=2,decimals=1,sign=false,
				borderwidth=0pt,backgroundcol=lightgray,approx=1, vertical=true, 
				vhead=true, scoreapprox=1
			}
		\end{center}
	\end{questionmultx}
\end{qcm}

\begin{qcm}{produit-scalaire}
	\begin{questionmultx}{C}
		
		\[ \frac{1}{2} \]
		\def\AMCntextVHead#1{%
			\edef\col{#1}
			\edef\head{%$
				\if\col0U\fi
				\if\col1D\fi
				\if\col2M\fi
				\if\col310M\fi
			}\emph{\head}}
		\begin{center}
			\emph{Arrondir la réponse si besoin.}\\
			\AMCnumericChoices{1/2}{digits=2,decimals=0,sign=false,
				borderwidth=0pt,backgroundcol=lightgray,approx=1, vertical=true, 
				vhead=true, scoreapprox=1
			}
		\end{center}
	\end{questionmultx}
\end{qcm}


\exemplaire{10}{

		

\centering\large\bf Erreurs d'arrondis
\bigskip
  


\begin{multicols}{2}
\restituegroupe{produit-scalaire}
\end{multicols}


}

\end{document}
