There are two cogwheels on a table. The bigger one has 10 teeth and is fixed to the table. The smaller one has 5 teeth and revolves around the bigger one. If the smaller cogwheel makes one full rotation around the bigger cogwheel, how many rotations will it make with respect to the table?

The answer is three rotations in total. Two because of the ratio 10:5, one more because of the movement of the smaller cogwheel.

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