(1/2)x+(2/3)x=(2/3).
(1/2)x+(2/3)x=(2/3)．
<gadget id="calculator">2 / 3</gadget>
<output>2/3 = around 0.666667</output>

<gadget id="calculator">1 / 2</gadget>
<output>1/2 = around 0.5</output>

<gadget id="calculator">(1/2) + (2/3)</gadget>
<output>7/6 = around 1.166667</output>

<gadget id="calculator">(2/3) / (7/6)</gadget>
<output>4/7 = around 0.571429</output>

<result>4/7 = around 0.571429</result>