Rows of numbers from top to bottom are: 5 8 4 11; 12 7 2; 9 5; 6 10 5; 8 6; 7 4 8 ?; 9 6 6; 10 4; 7. What number should replace the question mark? Answer with a natural number.
In each cross-shaped figure the corner numbers (top-left, top-right, bottom-left, bottom-right) and the centre number are: 4, 7, 4, 8 with 4 in the centre; 7, 6, 9, 2 with 40 in the centre; 6, 3, 9, 4 with ? in the centre. What number should replace the question mark? Answer with a natural number.
Each triangle has a number at the top and numbers at the bottom left and bottom right, and a number in the centre. The triangles are: top 3, left 9, right 5, centre 32; top 8, left 6, right 7, centre 55; top 7, left 5, right 9, centre ?. What number should replace the question mark? Answer with a natural number.
Each circle is divided into three parts with numbers: top 6, left 12, right 9; top 16, left 4, right 8; top 2, left 28, right ?. What number should replace the question mark? Answer with a natural number.