The circumference of a rectangular pool mouth is 140 meters, and the length is 30 meters more than the width. Use a water pipe that feeds 20 cubic meters per minute to feed water for 2 hours. How deep is the pool at this time?
一个长方形水池口周长为140米，长比宽多30米．用每分钟进水20立方米的水管进水2小时，这时池水深多少米？
<gadget id="calculator">140 / 2</gadget>
<output>70</output>

<gadget id="calculator">70 - 30</gadget>
<output>40</output>

<gadget id="calculator">40 / 2</gadget>
<output>20</output>

<gadget id="calculator">20 + 30</gadget>
<output>50</output>

<gadget id="calculator">20 * 50</gadget>
<output>1_000</output>

<gadget id="calculator">60 / 1_000</gadget>
<output>3/50 = around 0.06</output>

<gadget id="calculator">20 * 2 * (3/50)</gadget>
<output>12/5 = around 2.4</output>

<result>12/5 = around 2.4</result>