The addition of natural numbers

Operations with natural numbers I

11. Complete this five-pointed magic star.  

  Esta unidad interactiva requiere la máquina virtual de Java J2RE.

This five-pointed star is formed with natural numbers from 0 to 14.

The sum of the three numbers in each segment is equal to 21

To complete the star you may put the numbers on the segments where only one is needed.

There are 24 different five-pointed stars like this. Every time you click on Init a new star will appear at random.

  Eduardo Barbero Corral
Spanish Ministry of Education. Year 2007

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