In the task called Arithmetical City, the sample grid seems to be wrong: a solid arrow is pointing from the 43 in the last row to a 36, but 36 is not an integer multiple of 43.
It's pointing from the digit 4 only, not the whole 43, otherwise the line would be emanating from the edge of the oval
It's pointing from the digit
It's pointing from the digit 4 only, not the whole 43, otherwise the line would be emanating from the edge of the oval