Dig a cuboid pit at a construction site. This pit is 50 decimeters long and 30 decimeters wide, and a total of 45 cubic meters of soil was excavated. How deep is this pit?
建筑工地挖一个长方体土坑．这个坑长50分米，宽30分米，共挖土45立方米，这个土坑深多少分米？
<gadget id="calculator">50 * 30</gadget>
<output>1_500</output>

<gadget id="calculator">1_000 / 1_500</gadget>
<output>2/3 = around 0.666667</output>

<gadget id="calculator">45 * (2/3)</gadget>
<output>30</output>

<result>30</result>