For a children's car, the diameter of the front wheel is 0.3 meters, and the radius of the rear wheel is 0.12 meters. If the front wheel turns 12 times, how many times does the rear wheel turn?
一种儿童车，前轮直径为0.3米，后轮半径是0.12米，前轮转12周走的路，后轮要转多少周？
<gadget id="calculator">3.14 * 0.3 * 12</gadget>
<output>11.304</output>

<gadget id="calculator">2 * 3.14 * 0.12</gadget>
<output>0.7536</output>

<gadget id="calculator">11.304 / 0.7536</gadget>
<output>15</output>

<result>15</result>