Le Lejia went to school and walked 50 meters per minute. After walking for 2 minutes, he found that if he kept walking at this speed, he would be 8 minutes late for school. So Lele started to speed up, walking 10 meters more per minute than before, and when she arrived at the school, there were still 5 minutes before class. Q: How many kilometers is Lelejia from the school?
乐乐家去学校上学，每分钟走50米，走了2分钟后，发觉按这样的速度走下去，到学校就会迟到8分钟．于是乐乐开始加快速度，每分钟比原来多走10米，结果到达学校时离上课还有5分钟．问：乐乐家离学校多少千米．
<gadget id="calculator">50 * 2</gadget>
<output>100</output>

<gadget id="calculator">50 * 8</gadget>
<output>400</output>

<gadget id="calculator">50 + 10</gadget>
<output>60</output>

<gadget id="calculator">60 * 5</gadget>
<output>300</output>

<gadget id="calculator">400 + 300</gadget>
<output>700</output>

<gadget id="calculator">700 / 10</gadget>
<output>70</output>

<gadget id="calculator">70 - 5</gadget>
<output>65</output>

<gadget id="calculator">60 * 65</gadget>
<output>3_900</output>

<gadget id="calculator">100 + 3_900</gadget>
<output>4_000</output>

<result>4_000</result>