Hedong Township dug a 500-meter-long canal. The cross-section of the canal is a trapezoid, with a width of 1.8 meters at the top, a width of 10 decimeters at the bottom, and a depth of 6 decimeters. If 84 square meters of soil are excavated every day, how many days will it take to dig this canal?
河东乡挖一条直500米长的水渠，水渠的横截面是一个梯形，上口宽1.8米，下底宽10分米，深6分米．如果每天挖土84方，需要多少天才能挖成这条水渠？
<gadget id="calculator">10 / 10</gadget>
<output>1</output>

<gadget id="calculator">1.8 + 1</gadget>
<output>2.8</output>

<gadget id="calculator">6 / 10 / 2</gadget>
<output>3/10 = around 0.3</output>

<gadget id="calculator">500 / 84</gadget>
<output>125/21 = around 5.952381</output>

<gadget id="calculator">2.8 * (3/10) * (125/21)</gadget>
<output>5</output>

<result>5</result>