The distance from Xiao Ming's home to school is 4200 meters, and he walked 210 meters in 3 minutes. At this speed, how many minutes will it take him to walk from home to school?
小明家到学校的距离有4200米，他3分钟走了210米，照这样的速度，他从家到学校共要走多少分钟？
<gadget id="calculator">210 / 3</gadget>
<output>70</output>

<gadget id="calculator">4_200 / 70</gadget>
<output>60</output>

<result>60</result>