4x+(4/7)=1+(4/7).
4x+(4/7)=1+(4/7)．
<gadget id="calculator">4 / 7</gadget>
<output>4/7 = around 0.571429</output>

<gadget id="calculator">(4/7) - (4/7)</gadget>
<output>0</output>

<gadget id="calculator">1 + 0</gadget>
<output>1</output>

<gadget id="calculator">1 / 4</gadget>
<output>1/4 = around 0.25</output>

<result>1/4 = around 0.25</result>