Xiaohong's home is 307 meters away from the school. Xiaohong has to go back and forth twice a day. How many meters does she have to walk in total?
小红家离学校有307米，小红一天要往返两次，一共要走多少米？
<gadget id="calculator">307 * 2 * 2</gadget>
<output>1_228</output>

<result>1_228</result>