Henry Ernest Dudeney/Puzzles and Curious Problems/280 - The Ten Barrels

by : $280$

 * The Ten Barrels
 * A merchant had ten barrels of sugar, which he placed in the form of a pyramid, as shown.
 * Every barrel bore a different number, except one, which was not marked.


 * Dudeney-Puzzles-and-Curious-Problems-280.png


 * It will be seen that he had accidentally arranged them so that the numbers in the three sides added up alike --
 * that is, to $16$.
 * Can you arrange them so that the three sides shall sum to the smallest number possible?
 * Of course the central barrel (which happens to be $7$ in the diagram) does not come into the count.