It takes 6 hours for A and B to cooperate to complete a project. First, A works alone for 5 hours, and then B works alone for 3 hours. This is (7/10) of the total workload. If A alone completes all the work, how long will it take to complete?
一项工程，甲乙合作需要6小时完成．先由甲独做5小时，又由乙单独做3小时，这是完成了总工作量的(7/10)，如果由甲全部单独完成需几时完成？
<gadget id="calculator">7 / 10</gadget>
<output>7/10 = around 0.7</output>

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

<gadget id="calculator">(1/6) * 3</gadget>
<output>1/2 = around 0.5</output>

<gadget id="calculator">(7/10) - (1/2)</gadget>
<output>1/5 = around 0.2</output>

<gadget id="calculator">5 - 3</gadget>
<output>2</output>

<gadget id="calculator">(1/5) / 2</gadget>
<output>1/10 = around 0.1</output>

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

<result>10</result>