A bamboo pole is 3.5 meters long, inserted (1/4) meter into the river bottom mud, and (5/8) meters above the water surface, how deep is the river?
一根竹竿长3.5米，插入河底泥中(1/4)米，露出水面(5/8)米，这条河水深多少米？
<gadget id="calculator">1 / 4</gadget>
<output>1/4 = around 0.25</output>

<gadget id="calculator">5 / 8</gadget>
<output>5/8 = around 0.625</output>

<gadget id="calculator">3.5 - (1/4) - (5/8)</gadget>
<output>2.625</output>

<result>2.625</result>