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5. What figure should replace the question mark?
  3 8 6 30
4 9 3 39
7 5 2 ?
 

Explanation:
Column 4 = (Column 1 × Column 2 + Column 3). 30 = 3 × 8 + 6; 39 = 4 × 9 + 3; 37 = 7 × 5 + 2.