Struggle Primary School organizes sixth grade students to go to Baihua Mountain for camping and training, and the trip increases by 2 kilometers every day. It took 4 days when I went there, and 3 days when I came back. How many kilometers is the distance from the school to Baihua Mountain?
奋斗小学组织六年级同学到百花山进行野营拉练，行程每天增加2千米．去时用了4天，回来时用了3天，问学校距离百花山多少千米？
<gadget id="calculator">2 + 4 + 6</gadget>
<output>12</output>

<gadget id="calculator">8 + 10 + 12</gadget>
<output>30</output>

<gadget id="calculator">30 - 12</gadget>
<output>18</output>

<gadget id="calculator">18 * 3</gadget>
<output>54</output>

<gadget id="calculator">54 + 30</gadget>
<output>84</output>

<result>84</result>