meow
5: looking across, the sum of each pair of numbers is one more than the previous pair of numbers
128: reverse each number and add to produce the number in the centre, i.e. 61 + 41 + 26 = 128
156: 9 + 6 = 15 and 2 + 4 = 6
21: looking across and down each line of numbers, the first number in the middle is the sum of the first digits of the numbers in bold, and the second number in the middle is the sum of the second digits
6: respective columns total 22, 20, 18, 16, 14

6. What number should replace the question mark?











7. What number should replace the question mark?









8. What number is missing from the third bracket?







9. What number should replace the question mark?








10. What number should replace the question mark?











4

2

6

3

1

5

4

7

3

3

7

6

2

?

6

8

25 (149) 97
31 (611) 58
29 (???) 64

7
8
7

1
8
2
5

8
9
1

3
6
4
7

6
2
?

16

26

14

62

14

?

32

91

104

31

12

75

38

72

11

61

16

10

18

67

86

?

8

16

39

16

41

8

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