Xiao Ming's home is 1,570 meters away from school. He rides a bicycle home every day. The tire diameter of the bicycle is 50 cm. If the bicycle rotates 40 times per minute, how long will it take for Xiao Ming to get home?
小明家离学校有1570米，他每天骑自行车回家，自行车的轮胎直径是50厘米，如果自行车每分钟转40圈，小明多长时间可以到家？
<gadget id="calculator">50 / 100</gadget>
<output>1/2 = around 0.5</output>

<gadget id="calculator">3.14 * (1/2) * 40</gadget>
<output>62.8</output>

<gadget id="calculator">1_570 / 62.8</gadget>
<output>25</output>

<result>25</result>