התחבר/י באמצעות
- או -
\[\begin{aligned} 500-200=? \end{aligned}\]
\[\begin{aligned} 500-400=? \end{aligned}\]
\[\begin{aligned} 800-100=? \end{aligned}\]
\[\begin{aligned} 400+400=? \end{aligned}\]
\[\begin{aligned} 900+0=? \end{aligned}\]