(2/15)/(1-((1/5)+(1/3))).
(2/15)/(1-((1/5)+(1/3)))．
<gadget id="calculator">2 / 15</gadget>
<output>2/15 = around 0.133333</output>

<gadget id="calculator">1 / 5</gadget>
<output>1/5 = around 0.2</output>

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

<gadget id="calculator">(1/5) + (1/3)</gadget>
<output>8/15 = around 0.533333</output>

<gadget id="calculator">1 - (8/15)</gadget>
<output>7/15 = around 0.466667</output>

<gadget id="calculator">(2/15) / (7/15)</gadget>
<output>2/7 = around 0.285714</output>

<result>2/7 = around 0.285714</result>