(5/7)+(2/7)/2.
(5/7)+(2/7)/2．
<gadget id="calculator">5 / 7</gadget>
<output>5/7 = around 0.714286</output>

<gadget id="calculator">2 / 7</gadget>
<output>2/7 = around 0.285714</output>

<gadget id="calculator">(2/7) / 2</gadget>
<output>1/7 = around 0.142857</output>

<gadget id="calculator">(5/7) + (1/7)</gadget>
<output>6/7 = around 0.857143</output>

<result>6/7 = around 0.857143</result>