When you pedal for one turn, the wheel (front gear) also rotates for one turn. Suppose the wheel has m teeth and the flywheel (rear gear) has n teeth. Due to the chain drive, the flywheel also rotates by m teeth. The number of revolutions of the flywheel, that is, the number of revolutions of the wheel, is m: n, and then the distance can be obtained by multiplying it by the wheel circumference, that is, the distance for one cycle = the wheel circumference x (the number of teeth in the front gear: the number of teeth in the rear gear).