u-can-do

Petite 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. One number has been provided to get you started.  Find the remaining 4 numbers.

The Solution

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

Value 3 is provided and can not be reused.

Starting at Equation (1), unknowns A & B can only be equal to 1, 2, 5 or 6 as shown. All other combination include a 3 value.

Equation (2): unknown B can now be equal to 1, 2 or 5 only as shown Then C can only be equal to 4, 7, or 8.  Comparing with Equation (1), 6 is eliminated as a possible value for B, A can now only be equal to 2, 5 or 6.

Equation (3): unknowns C & D can only be equal 8 or 9 as shown. Therefore comparing with Equation (2), C must be equal to 8 & D equal to 9. With C equal to 8 in Equation (2), B must then be equal to 1 and with B equal to 1 in Equation (1), A must then be equal to 6.

Equation (4) confirms that if D is equal to 9 and A is equal to 6.

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

 

Contact: mathspuzzles@gordonburgin.com

© G R Burgin 2009