Problem of the Block
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Cross sums
Figure 1: Problems 1-2. Hexagon Each 3 node ‘spoke’ of the hexagon counts as one edge as well as the 3 node outer
edges. Use the numbers 1-19. Can you write it so each sum of 3 numbers in each edge adds to 22? to 23?
Figure 2: Problem 3. Lattice Select thirteen integers, of
which twelve are different, and place them in the lattice so each
3 node line adds to 20. (hint: the smallest number needed is
1, the largest is 15)
Figure 3: Problem 4. Star Can you place the numbers
1 through 12 in the nodes of the star so the sum across
each of the six lines is 26?
Turn in solutions to Dr. S in Law 204 or by email at tskorczewski@cornellcollege.edu by February 7, 2016. Solutions for only
one/some questions or partial solutions will receive credit (and are encouraged!). You can turn in a solution to just one puzzle
and turn in a solution to another one on a different day. Submitting solutions for the Problem of the Block can earn culture
points toward the major in mathematics. For more information about the Problem of the Block, including the current leaderboard for the yearly competition, and to print off your own copy visit http://www.cornellcollege.edu/mathematics/problemof-the-block/index.shtml.
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