A piece of fabric can be used to make 10 coats or 15 pairs of trousers. If you make 5 pairs of trousers first, and then match the rest of the fabric into a complete set (the cloth used for each garment remains the same), how many sets can you make?
一块布料，可做10件上衣或15条裤子，若先做5条裤子，剩下的布料再配成套(每件衣服用布都不变)，还可做多少套？
<gadget id="calculator">1 / 3</gadget>
<output>1/3 = around 0.333333</output>

<gadget id="calculator">1 - (1/3)</gadget>
<output>2/3 = around 0.666667</output>

<gadget id="calculator">1 / 6</gadget>
<output>1/6 = around 0.166667</output>

<gadget id="calculator">(2/3) / (1/6)</gadget>
<output>4</output>

<result>4</result>