Sum Pyramids – 3
These pyramids are called Sum Pyramids. The number above each pair of connected numbers is their sum.
THE CHALLENGE
Place some of the numbers from 1 to 15, not repeating any number, to complete this Sum Pyramid. Can you find more than one solution?
Notes
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THE CHALLENGE
Following the numbers up, 15 will equal 3 plus twice the middle number in the bottom row plus the leftmost number in the bottom row. So, 12 will be twice the middle number plus the leftmost number.
The possibilities for the bottom row are: (2 5 3), (4 4 3), (6 3 3), (8 2 3), and (10 1 3). This gives us three possible solutions:
(15)
(7 8)
(2 5 3)
or
(15)
(10 5)
(8 2 3)
or
(15)
(11 4)
(10 1 3)