\documentclass[xcolor={table,svgnames}]{beamer}
\usefonttheme[onlymath]{serif}
\setbeamertemplate{navigation symbols}{}
\usepackage{ProfCollege90}

\begin{document}
\QFlash[Daily]{%
  15/%
  $\times2$/%
  $-8$/%
  \scriptsize%
  \begin{tabular}{c}
    Moitié\\
    de
  \end{tabular}/%
  $\times4$/%
  $+1$/%
  $\div9$/%
  \scriptsize%
  \begin{tabular}{c}
    Prendre\\
    le carré%
  \end{tabular}/%
  $-7$,
  }
\end{document}