Xiao Ming's home is 1.57 kilometers away from the school, and the diameter of the bicycle tire is 50 cm. If the bicycle turns 80 times per minute, how long will it take Xiao Ming to get home?
小明家离学校有1.57千米，自行车轮胎直径是50厘米，如果自行车每分钟转80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) * 80</gadget>
<output>125.6</output>

<gadget id="calculator">1_000 / 125.6</gadget>
<output>7.961783</output>

<gadget id="calculator">1.57 * 7.961783</gadget>
<output>12.499999</output>

<result>12.499999</result>