Xiaoxin has to walk 1.2 kilometers from home to school. Today he walked 0.4 kilometers and then went home to pick up a book before going to school. How much more kilometers would he walk than usual?
小新从家到学校要走1.2千米．今天他走了0.4千米后又回家取一本书再去上学，这样他比平时要多走多少千米？
<gadget id="calculator">0.4 + 0.4</gadget>
<output>0.8</output>

<result>0.8</result>