5 excavators work 8 hours a day, and can dig a ditch 40 meters long, 20 meters wide, and 3 meters deep in 4 days; 6 excavators work 5 hours a day to dig a ditch 100 meters long, 15 meters wide, How many days will it take for a ditch of 3 meters?
5台挖土机每天工作8小时，4天可挖长40米、宽20米、深3米的一条沟，6台挖土机每天工作5小时，要挖长100米、宽15米、深3米的一条沟，需要多少天．
<gadget id="calculator">3 / 4 / 5 / 8</gadget>
<output>3/160 = around 0.01875</output>

<gadget id="calculator">40 * 20 * (3/160) * 6</gadget>
<output>90</output>

<gadget id="calculator">3 / 90 / 5</gadget>
<output>1/150 = around 0.006667</output>

<gadget id="calculator">100 * 40 * 20 * (3/160) * (1/150)</gadget>
<output>10</output>

<result>10</result>