A book, I read the whole book (4/17) in the first three days, and read the whole book in the next four days (6/17). How much of this book is naughty?
一本书，我前三天看了全书的(4/17)，后四天看了全书的(6/17)．这本书淘气还剩几分之几没看完？
<gadget id="calculator">4 / 17</gadget>
<output>4/17 = around 0.235294</output>

<gadget id="calculator">6 / 17</gadget>
<output>6/17 = around 0.352941</output>

<gadget id="calculator">1 - (4/17) - (6/17)</gadget>
<output>7/17 = around 0.411765</output>

<result>7/17 = around 0.411765</result>