The distance from Beibei’s home to school is 0.8 kilometers. One day Beibei went to school from home to school. When he walked a kilometer, he found that he forgot to take the pencil case, so he immediately turned around and went home to take the pencil case to school. How many kilometers did Beibei walk from home to school this time?
贝贝家到学校的距离是0.8千米，一天贝贝上学从家出发去学校，当走了a千米时发现忘记拿文具盒，于是立即转身回家拿上文具盒去学校．贝贝这次从家去学校共走了多少千米．
<gadget id="calculator">0.8 + 2</gadget>
<output>2.8</output>

<result>2.8</result>