(3/4) minus the sum of (2/5) and (1/4), what is the difference?
(3/4)减去(2/5)与(1/4)的和，差是多少？
<gadget id="calculator">3 / 4</gadget>
<output>3/4 = around 0.75</output>

<gadget id="calculator">2 / 5</gadget>
<output>2/5 = around 0.4</output>

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

<gadget id="calculator">(2/5) + (1/4)</gadget>
<output>13/20 = around 0.65</output>

<gadget id="calculator">(3/4) - (13/20)</gadget>
<output>1/10 = around 0.1</output>

<result>1/10 = around 0.1</result>