Each lap of the school playground is 0.4 kilometers, Xiao Ming ran 4 laps. How many kilometers did he run in total?
学校操场每圈为0.4千米，小明跑了4圈．他一共跑了多少千米？
<gadget id="calculator">0.4 * 4</gadget>
<output>1.6</output>

<result>1.6</result>