What is the sum of (9/10) minus (1/4) and (3/5)
(9/10)减去(1/4)与(3/5)的和列式为多少
<gadget id="calculator">9 / 10</gadget>
<output>9/10 = around 0.9</output>

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

<gadget id="calculator">3 / 5</gadget>
<output>3/5 = around 0.6</output>

<gadget id="calculator">(1/4) + (3/5)</gadget>
<output>17/20 = around 0.85</output>

<gadget id="calculator">(9/10) - (17/20)</gadget>
<output>1/20 = around 0.05</output>

<result>1/20 = around 0.05</result>