\documentclass[a4paper,10pt]{classPres}

\usetikzlibrary{snakes}

\author{}
\title{}
\date{}

\begin{document}
\begin{frame}{Calcul mental}
    \begin{center}
        \huge 30 secondes par calcul
    \end{center}
\end{frame}

\begin{frame}{Calcul 1}
    \huge
    \[
        47 \times 9 =
    \]
\end{frame}

\begin{frame}{Calcul 2}
    \huge
    Comment est l'angle $\widehat{D0B}$?
    \begin{center}
        \begin{tikzpicture}[scale=1.4]
            \draw (0.6, 0.3) node {O};
            \foreach \angle/\letter in {0/A, 1/B, 2/C, 3/D, 4/E, 5/F, 6/G, 7/H}
            {
                \draw [very thick] (0, 0) -- ({\angle*45}: 2) node[rotate={\angle*45}] {x} node[above right] {\letter} -- ({\angle*45}: 2.3);
            }
        \end{tikzpicture}
    \end{center}
\end{frame}

\begin{frame}{Calcul 3}
    \LARGE
    Compléter la valeur manquante

    \begin{center}
        \begin{tabular}{|c|*{2}{p{2cm}|}}
        \hline
        Nombre de sacs & 2 & 6 \\
        \hline
        Prix & ... & 18 \\
        \hline
    \end{tabular}
    \end{center}
\end{frame}

\begin{frame}{Calcul 4}
    \LARGE
    Calculer l'aire de la figure
    \begin{center}
        \begin{tikzpicture}
            \filldraw[very thick, fill=blue!60]
                (4,4) -- node[midway, sloped, above]{5cm}
                (4,-1) -- node[midway] {o} node[midway, below]{3cm}
                (1,-1) -- node[midway] {x} node[midway, right] {2cm}
                (1,0) --  node[midway] {x} 
                (-1,0) -- node[midway] {o}
                (-1,3) --  node[midway] {x} 
                (1,3) -- node[midway] {x} 
                (1,4) -- node {o}
                cycle;
                \draw[dotted, very thick] (1,-1) -- (-1, -1) -- (-1, 0);
                \draw[dotted, very thick] (-1,3) -- (-1, 4) -- (1, 4);
        \end{tikzpicture}
    \end{center}
\end{frame}

\begin{frame}{Fin}
    \begin{center}
        \huge On retourne son papier.
    \end{center}
\end{frame}


\end{document}