It takes 30 days for team A to repair a section of railway alone, and the work efficiency of team B is that of A (4/5). How many days can the two teams complete together?
修一段铁路，甲队单独修用30天完成，乙队的工作效率是甲的(4/5)．两队合修，几天可以完成？
<gadget id="calculator">1 / 30</gadget>
<output>1/30 = around 0.033333</output>

<gadget id="calculator">4 / 5</gadget>
<output>4/5 = around 0.8</output>

<gadget id="calculator">(1/30) * (4/5)</gadget>
<output>2/75 = around 0.026667</output>

<gadget id="calculator">(1/30) + (2/75)</gadget>
<output>3/50 = around 0.06</output>

<gadget id="calculator">1 / (3/50)</gadget>
<output>50/3 = around 16.666667</output>

<result>50/3 = around 16.666667</result>