Starting in the top left and moving in a Z shape around the diagram, each number equals the sum of the previous 2 numbers.

The numbers in the segments of the top left circle equal the sum of the numbers in corresponding segments of the lower two circles, and the numbers in the top right circle equal the difference between numbers in corresponding segments of the lower two circles.

Starting with the bottom line of the triangle and moving up, the sum of the digits in each line decreases by 5 each time, from 20 to 5.

Numbers in the squares of the top middle figure equal the sum of the numbers in corresponding squares of the other 3 figures.

Starting at the top left and working down, then to the right and up, and finally to the right and down in a zig-zag shape, numbers follow the repeated sequence, subtracting 1 then adding 3 etc.