Solution 88188c96-7fcf-42c5-b946-13911acfe943

Points: 1 pt

The units digit is insufficient because
\[
25 > 8
\]

We see that
\[
25 = 3(8) + 1.
\]

Visually,

\begin{tikzpicture}[x=0.42cm,y=0.42cm]
  % top box
  \draw[rounded corners=1pt, gray!70, line width=0.5pt] (0,0) rectangle (8,1);
  \foreach \i in {0.5,1.5,...,7.5} {
    \fill (\i,0.5) circle (0.09);
  }

  % middle box
  \draw[rounded corners=1pt, gray!70, line width=0.5pt] (0,-1.6) rectangle (8,-0.6);
  \foreach \i in {0.5,1.5,...,7.5} {
    \fill (\i,-1.1) circle (0.09);
  }

  % bottom box
  \draw[rounded corners=1pt, gray!70, line width=0.5pt] (0,-3.2) rectangle (8,-2.2);
  \foreach \i in {0.5,1.5,...,7.5} {
    \fill (\i,-2.7) circle (0.09);
  }

  % leftover dot
  \fill (9.4,-1.1) circle (0.09);
\end{tikzpicture}

Final answer:
31_8