A batch of fabric can be made into 20 pieces of jackets, and 30 pieces of trousers. How many sets of clothes can be made from this batch of fabrics?
一批布料，做上衣可以做20件，如果做裤子可以做30条，这批布料可以做多少套衣服．
<gadget id="calculator">1 / 20</gadget>
<output>1/20 = around 0.05</output>

<gadget id="calculator">1 / 30</gadget>
<output>1/30 = around 0.033333</output>

<gadget id="calculator">(1/20) + (1/30)</gadget>
<output>1/12 = around 0.083333</output>

<gadget id="calculator">1 / (1/12)</gadget>
<output>12</output>

<result>12</result>