A and B work together to do a job. When the job is finished, A has completed (3/5) of the job. It is known that A alone will take 10 hours to do the job. How many hours will B need to do it alone?
甲、乙合做一件工作，完工时，甲完成了这件工作的(3/5)，已知这件工作甲单独做用10小时，问乙单独做要多少小时？
<gadget id="calculator">3 / 5</gadget>
<output>3/5 = around 0.6</output>

<gadget id="calculator">1 - (3/5)</gadget>
<output>2/5 = around 0.4</output>

<gadget id="calculator">1 / 10</gadget>
<output>1/10 = around 0.1</output>

<gadget id="calculator">(3/5) / (1/10)</gadget>
<output>6</output>

<gadget id="calculator">(2/5) / 6</gadget>
<output>1/15 = around 0.066667</output>

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

<result>15</result>