The number in each square represents the sum of the numbers in the four surrounding circles. The numbers in the circles can only be 1 to 9 and each number can be used only once. Three numbers have been provided to get you started. Find the remaining six numbers.
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Solution
Solution explanation
Comments on solving the puzzle; a process of eliminating possible values as answers:
Values 3, 4 & 7 are provided and can not be reused.
Starting at Equation (1), unknowns B & D can only be equal to 6 or 9 as shown. All other combinations include either a 3, 4 or 7 value.
Equation (2): unknowns D, F & E can only be equal to 1, 8 or 9 as shown since values 3, 4 & 7 can not be reused. Therefore comparing with Equation (1), D can only be equal to 9 and E & F can be equal to 1 or 8. Comparing with Equation (1), B is then equal to 6.
Equation (3): unknowns C & E can be equal 5 or 8 as shown. Comparing with Equation (2), E can only be equal to 8 & C is then equal to 5.
Equation (4): unknowns A, B & C can only be equal to 2, 5 or 6 as shown. Therefore comparing with Equation (1), (2) & (3) with B equal to 6, C is then equal to 5 and A is equal to 2.
Now insert your final answers into the original puzzle and verify the resulting sums.
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