A project can be completed in 10 days by A alone, and (1/3) of the project can be completed by B in 4 days alone. If A and B cooperate, how many days can the project be completed?
一项工程，甲独做10天完成，乙独做4天完成这项工程的(1/3)．如果甲、乙合作，多少天能完成这项工程？
<gadget id="calculator">1 / 10</gadget>
<output>1/10 = around 0.1</output>

<gadget id="calculator">1 / 3</gadget>
<output>1/3 = around 0.333333</output>

<gadget id="calculator">(1/3) / 4</gadget>
<output>1/12 = around 0.083333</output>

<gadget id="calculator">(1/10) + (1/12)</gadget>
<output>11/60 = around 0.183333</output>

<gadget id="calculator">1 / (11/60)</gadget>
<output>60/11 = around 5.454545</output>

<result>60/11 = around 5.454545</result>