21
30
27
The numbers at the vertices add up to the numbers
in the rectangles between them.
What number does each question mark represent?
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Topics: Starter  Algebra  Arithmetic  Puzzles
Arithmagons starter from Transum. pic.twitter.com/4og2Nz6EI9
— Jenny Howard (@J3nnyHoward) March 16, 2016
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The numbers at the vertices are 9, 12 and 18.
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