A rope, (2/5) and 15 meters are used, and the remaining (3/2) is used at this time, how many meters is the length of this rope?
一根绳，用去(2/5)又15米，这时用去的是余下的(3/2)，求这根绳长有多少米？
<gadget id="calculator">3 / 5</gadget>
<output>3/5 = around 0.6</output>

<gadget id="calculator">2 / 5</gadget>
<output>2/5 = around 0.4</output>

<gadget id="calculator">(3/5) - (2/5)</gadget>
<output>1/5 = around 0.2</output>

<gadget id="calculator">15 / (1/5)</gadget>
<output>75</output>

<result>75</result>