2012 Fermat Problem 22

In the country of Nohills, each pair of cities is connected by a straight (and flat) road. The chart to the right shows the distances along the straight roads between some pairs of cities. The distance along the straight road between city P and city R is closest to

\begin{array}{|c|c|c|c|c|}\hline & P & Q & R & S \\ \hline P & 0 & 25 & & 24 \\ \hline Q & 25 & 0 & 25 & 7 \\ \hline R & & 25 & 0 & 18 \\ \hline S & 24 & 7 & 18 & 0 \\ \hline\end{array}

\textbf{(A)}\ 30\quad \textbf{(B)}\ 25\quad \textbf{(C)}\ 27\quad \textbf{(D)}\ 24.5\quad \textbf{(E)}\ 24

If there are no answer choices shown, enter a numerical answer.

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