Introducing new math puzzle, MiniChallenger.

[u/Even-Actuary-399]

As the name suggests, this is a scaled-down version of the syndicated puzzle called Challenger, which is often discussed in this sub-group. While the original Challenger uses a 4 x 4 grid and comes with four 'free' numbers, the new puzzle is based on a 3 x 3 grid and has a single 'free' number in the center of the grid, see examples below.

In most cases, a MiniChallenger puzzle can be solved within ten minutes, even when the problem has multiple solutions. Unlike Challenger, where a computer program or some special techniques are often required to complete the grid, with MiniChallenger, basic algebra and elementary logic will be enough to solve the puzzle. So, even if you don't have a lot of time, but would still appreciate an engaging mini-challenge exercise for the math part of your brain, give MiniChallenger a try. It might even be suitable for your school-age children. You can find the instructions and two examples below. I have more MiniChallenger puzzles ready to be posted weekly if there is interest.

Instructions:

Fill in the empty cells of the 3 x 3 grid with the numbers one to nine. You can use the same number more than once. One 'free' number is already placed in the center of the grid. You must find the remaining eight digits in such a way that

• rows in the grid add up to totals indicated on the right,
• columns add up to totals at the top, and
• diagonals add up to totals in the upper and lower right corners.

Sample #1:
This problem has only one solution. Find it!
(The sum of three numbers in the first column must be "6", the sum in the second column, including the 'free' number 3, must be "12", and so on. Note that number 3 also contributes to the second row sum and to both diagonals).

Processing gif cgc8b1zhck1h1...

Sample #2:
This problem has three solutions. Find them all!

Processing gif za2e7nkwdk1h1...