The number 179 should be in place of the question mark. If you move clockwise starting from 3, then each subsequent number is equal to twice the previous one, to which you added 1, 3, 5, 7, 9.
3 × 2 + 1 = 7.
7 × 2 + 3 = 17.
17 × 2 + 5 = 39.
39 × 2 + 7 = 85.
85 × 2 + 9 = 179.
Instead of a question mark, there should be the number 11. To get each number from the left half of the circle, we take a number from the opposite sector, double it and add one.
5 = 2 × 2 + 1.
7 = 3 × 2 + 1.
9 = 4 × 2 + 1.
11 = 5 × 2 + 1.
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