u-can-do

CIRCLE-Sum Walkthrough

by G R Burgin

The Puzzle

The number within the 4 sectors of the outer circle is equal to the sum of the three numbers in its sector.  The numbers in the individual circles can only be 1 to 9 and each number can be used only once. Two numbers have been provided to get you started.  Find the remaining 6 numbers.

The Solution

Comments on Solving Puzzle – a process of eliminating possible values as answers:

C & F are given as 5 & 4 respectively and their values can not reused.

Starting at Equation (1), unknowns A & B can be equal  to 1 or 3 only as shown. Therefore, D, E, G & H can not be equal to 1, 3, 4 or 5.

Equation (2): unknowns D & E can be equal to 2 or 8 only as shown. All other combinations include either a 1, 3, 4 or 5 value.

Equation (3): unknowns E & G can be equal to 6, 7, 8 or 9 as shown. Therefore, comparing with Equation (2), E can only be equal to 8 & D is equal to 2 & G is equal to 7.

Equation (4): unknowns G, H & A can be equal to 3, 6 or 7 as shown. Comparing Equations (1), (2) & (3) and G is equal to 7.  Then H must be equal to 6, A equal to 3 & B equal to 1.  The value 9 is not used in the final solution of this puzzle example.

Now insert your final answers into the original puzzle and verify the resulting sums.

 

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© G R Burgin 2009