When a typist enters a manuscript, A can complete it in 4 hours, and B can complete it in 8 hours. Two people record at the same time, how many hours can it be completed?
打字员录入一份稿件，甲单独录入4小时可完成，乙单独录入8小时可完成．两人同时录入，几小时可以完成？
<gadget id="calculator">1 / 4</gadget>
<output>1/4 = around 0.25</output>

<gadget id="calculator">1 / 8</gadget>
<output>1/8 = around 0.125</output>

<gadget id="calculator">(1/4) + (1/8)</gadget>
<output>3/8 = around 0.375</output>

<gadget id="calculator">1 / (3/8)</gadget>
<output>8/3 = around 2.666667</output>

<result>8/3 = around 2.666667</result>