Xiao Ming's home is 425 meters away from school. He goes to and from school twice a day. How many meters does he have to walk in total?
小明家到学校有425米，他每天上学往返2个来回，一共要走多少米．
<gadget id="calculator">2 * 2</gadget>
<output>4</output>

<gadget id="calculator">425 * 4</gadget>
<output>1_700</output>

<result>1_700</result>