Support charity, get puzzles!
Patron Puzzles for Philanthropy

Monday Mutant 62: Crowd Nine (equations)

In this Crowd Nine puzzle, all of the outlined equations, when read from left to right or from top to bottom, must be true when the grid is filled in. Perform operations in reading order (for example, 3-1+2 is 4, not 0, and 1+2×3 is 9, not 7). The rules are otherwise unchanged.
This puzzle was written as a response to Mah Boy's puzzle which I reviewed in Grant's Review Corner: Volume 3. While I suspect that someone like motris could create a much better one of these, it does illustrate the concepts which I wanted to get across: the presentation is precise, with the rules and equations being clearly delineated, the givens are symmetrical (which almost never hurts), and the equations interact in different ways (see the overlapping equations in column 9).

4 comments

Paul K said...

Wow. I felt like I steadily progressed through this thing but when I was done, I had used the better part of an hour. Not sure if I ignored some the sudoku elements for too long or if it's just that hard or if I'm just that slow.

Blaine said...

The only complaint I would have about this format is that the boxes are rather small (to make room for the operators) making it hard to easily note the possible answers. This can be easily remedied by printing it in a larger size, so it isn't a big complaint.

I liked some of the logic you used. Most of the solving involved the equations first, then the rest was standard Sudoku logic.

Grant Fikes said...

Blaine: Pixelwise, the boxes are the same size as usual (at least if you "click to enlarge", a directive which people seem to never notice). I just added space between them.

David S said...

That top row. Was. Brilliant.

Blog Archive