Find the unknown (3/4): X=0.8: (1/7).
求未知数(3/4)：X=0.8：(1/7)．
<gadget id="calculator">3 / 4</gadget>
<output>3/4 = around 0.75</output>

<gadget id="calculator">1 / 7</gadget>
<output>1/7 = around 0.142857</output>

<gadget id="calculator">(3/4) * (1/7)</gadget>
<output>3/28 = around 0.107143</output>

<gadget id="calculator">(3/28) / 0.8</gadget>
<output>0.133929</output>

<result>0.133929</result>