Two gears, the diameter of one of which is 6cm, when the other gear rotates once, it needs to rotate 3 times, then the diameter of the other gear is . How many
两个齿轮，其中一个齿轮的直径是6cm，当另一个齿轮转动一周时，它需转动3周，则另一个齿轮的直径是．多少
<gadget id="calculator">3.14 * 6 * 3</gadget>
<output>56.52</output>

<gadget id="calculator">56.52 / 3.14</gadget>
<output>18</output>

<result>18</result>