So I have this Mensa Puzzle Calendar. Usually I can figure out the puzzles. Sometimes for the word puzzles I cheat, but I’ve never had a problem with the math puzzles. Until the one for Tuesday 6 October 2009. The only way I could solve it was by trail and error. I was thinking that there should be a smarter way using algebra, but I’m stumped. Does anyone else have an elegant solution?

Here is the puzzle (my diagram should appear in a monospace font in your browser window, if not, sorry, it will probably be impossible to read)

```
o
/ \
Side / \ Side
A o-----o B
/ \ / \
/ \ / \
o-----o-----o
Side C
```

Place the numbers 1-6 in the circles so that the following rules are obeyed:

[ul]

[li]The sum of the 3 inner circles = 1 more than the sum of the 3 circles on side A[/li][li]The sum of the 3 inner circles = 2 more than the sum of the 3 circles on side B[/li][li]The sum of the 3 circles on side C + the sum of the circles at the points of the big triangle = 1 more than the sum of the 3 inner circles.[/li][/ul]