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Weekly Problem 21 - 2008

Stage: 3 and 4 Challenge Level: Challenge Level:1
Grid

One of the digits 1 to 9 is put in each unshaded square so that no digit is repeated and the totals of the entries in the rows and columns are as shown. What number goes in the starred square?

 

 

 

If you liked this problem, here is an NRICH task which challenges you to use similar mathematical ideas.

 

 

This problem is taken from the UKMT Mathematical Challenges.

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