Calculation: 0.5-(1/3)+(1/4)=how much.
计算：0.5-(1/3)+(1/4)=多少．
<gadget id="calculator">1 / 3</gadget>
<output>1/3 = around 0.333333</output>

<gadget id="calculator">0.5 - (1/3)</gadget>
<output>0.166667</output>

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

<gadget id="calculator">0.166667 + (1/4)</gadget>
<output>0.416667</output>

<result>0.416667</result>