A project can be completed by the master alone in 8 hours and by the apprentice in 12 hours alone. How many hours can the task be completed if the master and apprentice cooperate?
一项工程，师傅单独做8小时完成，徒弟单独做12小时完成．师徒两人合作，多少小时可以完成任务？
<gadget id="calculator">1 / 8</gadget>
<output>1/8 = around 0.125</output>

<gadget id="calculator">1 / 12</gadget>
<output>1/12 = around 0.083333</output>

<gadget id="calculator">(1/8) + (1/12)</gadget>
<output>5/24 = around 0.208333</output>

<gadget id="calculator">1 / (5/24)</gadget>
<output>24/5 = around 4.8</output>

<result>24/5 = around 4.8</result>