Magic Hexagon
In the hexagons below, place the numbers 119 so that rows, columns and diagonals all add up to 38.
(Source: Eric W. Weisstein)

Extensions 
Place the numbers 119 in the circles so the sum of each of the rows with three circles around the outside is 23 and the sum of each of the rows with five circles through the middle is 40.
(Source: Jon Basden)
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