Read a book naughtily, read (1/3) of the whole book on the first day, and (1/2) of the whole book on the second day, what percentage of the whole book is left?
淘气看一本书，第一天看了全书的(1/3)，第二天看了全书的(1/2)，还剩全书的几分之几没看？
<gadget id="calculator">1 / 3</gadget>
<output>1/3 = around 0.333333</output>

<gadget id="calculator">1 / 2</gadget>
<output>1/2 = around 0.5</output>

<gadget id="calculator">(1/3) + (1/2)</gadget>
<output>5/6 = around 0.833333</output>

<gadget id="calculator">1 - (5/6)</gadget>
<output>1/6 = around 0.166667</output>

<result>1/6 = around 0.166667</result>