Subtract the sum of (4/15) and (1/3) from (9/10). What is the difference?
从(9/10)里减去(4/15)与(1/3)的和，差是多少？
<gadget id="calculator">9 / 10</gadget>
<output>9/10 = around 0.9</output>

<gadget id="calculator">4 / 15</gadget>
<output>4/15 = around 0.266667</output>

<gadget id="calculator">1 / 3</gadget>
<output>1/3 = around 0.333333</output>

<gadget id="calculator">(4/15) + (1/3)</gadget>
<output>3/5 = around 0.6</output>

<gadget id="calculator">(9/10) - (3/5)</gadget>
<output>3/10 = around 0.3</output>

<result>3/10 = around 0.3</result>