Numberskull is an original puzzle from TopAccolades.
Place the 9 numbers in the bottom-right corner onto the empty white squares, and any of the four arithmetic operators onto the empty grey squares to complete 6 equations - 3 left-to-right and 3 top-to-bottom.
There is always a unique solution. The answer can be found methodically, with no guessing required, using arithmetic and, if appropriate, logic, to determine the positions of the numbers.
The puzzle on the left has the solution shown on the right. These images are taken from the implementation of Numberskull found in the CompactPuzzles and CompactNumbers packages of CompactFun.
You can find out more about Numberskull puzzles, see examples, and learn more about the ability of TopAccolades to produce them for newspapers and magazines at:
Numberskull is a registered trademark of TopAccolades Limited in the UK.