Numbers Puzzles

11. Which number is missing?
  What is the next number?
Answer
6
Multiply the two outer numbers in each segment and divide by 2 then 3, alternately, putting the result at the centre of the opposite segment.
12. Which number is odd one out?
  What is the next number?
Answer
410
In all the other numbers, the first two digits added together give the third.
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