1-9. Fill in the nine parts of the five Olympic rings with nine numbers so that the sum of the numbers in each ring is 13. What is the number of each part?
There are two different filling methods to exclude duplicate solutions, as shown in the figure below:
Fill 9 numbers 1 to 9 in the circle so that the sum of 3 numbers on each triangle and line is equal
Or
Put nine numbers from 1 to 9 in the circle: () + () = () - () = () * () = ()
1+7=8
9-4=5
2*3=6