Enter the numbers in the circle so that the numbers on each line equal the sum of the numbers at each end.

problem: I think that this will involve problem solving

clarify: NO clarifications

STEPS

1. the number on the left in the middle is 12 the number on the right in the middle is 18 and the bottom middle number is 18

2.so I first had to find out what plus what equals twelve

3. so the answers I got were

10+2 8+4 9+3 7+5 6+6

4. so I first tried 10 + 2 the 10 on the top and then the 2 at the bottom then i had to figure out what plus two equals 18 the answer was 16

5. that obviously is not correct

6. so then I tried with 9+3 too large

7. so then I tried 8+4 it was still to big

8. so I then decided to move down 2 more so I went to 6+6

9. then I realised that was right because 6+6 is 12 and I did not have to switch the number at all because it has the exact same number

10. so then I has to figure out what plus 6 is 18 and the answer is 12

11. so in the end it will look like this

at the very top a 6 then in the middle on the left hand side is 12 then on the right hand side in the middle is 18 then on the very far left corner is 6 then on the very far left hand side is 12

solution: I believe that this involved guess check and improve.