ARITHMAGONS

Arithmagons are number puzzles made from triangles. The circled numbers are added together to give the number on the line joining the circles. The challenge is to find the correct numbers to go inside the circles.

Find the numbers missing from the circles in this arithmagon:

Solution

Think about the pairs of numbers that add together to give the numbers on the lines.

11 = 10 + 1 = 9 + 2 = 8 + 3 = 7 + 4 = 6 + 5

10 = 9 + 1 = 8 + 2 = 7 + 3 = 6 + 4 = 5 + 5

5= 4 + 1 = 3 + 2

Now, by trial and error, write numbers in the circles to reach a solution:

11 = 10 + 1? 11 = 9 + 2 ? 11 = 8 + 3 ?