A project can be done by team A alone in 5 hours and by team B in 6 hours. Team A did it for 3 hours first, and then Team B did it. How many hours will it take to finish?
一项工程，甲队单独做要5小时，乙队单独做要6小时．甲队先做了3小时，然后由乙队去做，还要几小时才能完成？
<gadget id="calculator">1 / 5</gadget>
<output>1/5 = around 0.2</output>

<gadget id="calculator">(1/5) * 3</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 / 6</gadget>
<output>1/6 = around 0.166667</output>

<gadget id="calculator">(2/5) / (1/6)</gadget>
<output>12/5 = around 2.4</output>

<result>12/5 = around 2.4</result>