Character Puzzles - General Questions

Find the missing number:

9   1   18
5   4   25
2   1   ?

Find the missing number:

6   3   24
7   6   49
8   2   ?

Find the missing number:

5   1   12
9   8   34
4   1   ?

Find the missing number:

4   2   12
4   1   8
8   3   ?

Find the missing number:

2   1   4
8   7   64
5   4   ?