In order to improve the physical fitness of the students, the school organized the students to go hiking for an outing. They walked a total of 5.5 kilometers. Among them, the mountain road was 2.1 kilometers per hour, and the flat road was 3.1 kilometers per hour. They walked for 0.7 hours. How many hours did you walk on the road?
为了提高学生的身体素质，学校组织学生进行徒步郊游活动，一共走了5.5千米的路程，其中山路每小时行2.1千米，平路每小时行3.1千米，走了0.7小时的山路，平路走了多少小时？
<gadget id="calculator">2.1 * 0.7</gadget>
<output>1.47</output>

<gadget id="calculator">5.5 - 1.47</gadget>
<output>4.03</output>

<gadget id="calculator">4.03 / 3.1</gadget>
<output>1.3</output>

<result>1.3</result>