A children's clothing factory produces a kind of children's clothing. It produces 260 sets in the first week, 190 sets in the second week, and uses 140 meters less cloth in the second week than in the first week. How many meters of cloth was used in the first week?
童装厂生产一种童装，第一周生产260套，第二周生产190套，第二周比第一周少用布140米．第一周用布多少米？
<gadget id="calculator">260 - 190</gadget>
<output>70</output>

<gadget id="calculator">140 / 70</gadget>
<output>2</output>

<gadget id="calculator">2 * 260</gadget>
<output>520</output>

<result>520</result>