If it costs 405 yuan to buy 6 schoolbags and 3 boxes of colored pens, and 165 yuan to buy 2 schoolbags and 3 boxes of colored pens, how much is a schoolbag?
如果买6个书包和3盒彩笔要405元，买2个书包和3盒彩笔要165元，那么一个书包是多少元钱？
<gadget id="calculator">405 - 165</gadget>
<output>240</output>

<gadget id="calculator">6 - 2</gadget>
<output>4</output>

<gadget id="calculator">240 / 4</gadget>
<output>60</output>

<result>60</result>