(9/10)+(1/2)-(9/10)+(1/2)=how much
(9/10)+(1/2)-(9/10)+(1/2)=多少
<gadget id="calculator">9 / 10</gadget>
<output>9/10 = around 0.9</output>

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

<gadget id="calculator">(1/2) - (9/10)</gadget>
<output>-2/5 = around -0.4</output>

<gadget id="calculator">(9/10) + (-2/5) + (1/2)</gadget>
<output>1</output>

<result>1</result>