Solve the equation: 0.4: x=(1+(1/7)):1.
解方程：0.4：x=(1+(1/7))：1．
<gadget id="calculator">1 / 7</gadget>
<output>1/7 = around 0.142857</output>

<gadget id="calculator">1 + (1/7)</gadget>
<output>8/7 = around 1.142857</output>

<gadget id="calculator">0.4 / (8/7)</gadget>
<output>0.35</output>

<result>0.35</result>