Centers Sum

[gabriele]

I need your suggestions

Do you think that this scheme is too difficult?

the sum of the yellow cells both in horizontal that vertical it is always equal

[rakesh_rai]

It took a while to understand the rules. Initially I thought it was the same as neighbours. Then I thought it was the same as magic square. Later I found that this indeed is similar to magic square but not the same. The given example is easy, though (4.40).

Based on the given grid, it does not seem too difficult - the main challenge is to find out the sum of the yellow cells in a row/column. Once it is found out, the grid solves easily.