Aunt Wang bought a piece of cloth, which can be used to make 20 coats or 30 pairs of trousers. Now make 6 pairs of trousers first, how many pieces can be made if all the remaining cloth is used as tops?
王大妈买了一块布，可以做20件上衣，或者30条裤子．现在先做了6条裤子，余下的布如果全部做上衣可以做多少件？
<gadget id="calculator">1 / 30</gadget>
<output>1/30 = around 0.033333</output>

<gadget id="calculator">(1/30) * 6</gadget>
<output>1/5 = around 0.2</output>

<gadget id="calculator">1 - (1/5)</gadget>
<output>4/5 = around 0.8</output>

<gadget id="calculator">1 / 20</gadget>
<output>1/20 = around 0.05</output>

<gadget id="calculator">(4/5) / (1/20)</gadget>
<output>16</output>

<result>16</result>