A story book, Xiaoling read the whole book (1/3) on the first day, read 21 pages on the second day, and left 47 pages unread. How many pages does this book have?
一本故事书，小玲第一天读了全书的(1/3)，第二天读了21页，还有47页没有读．这本书一共有多少页？
<gadget id="calculator">21 + 47</gadget>
<output>68</output>

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

<gadget id="calculator">1 - (1/3)</gadget>
<output>2/3 = around 0.666667</output>

<gadget id="calculator">68 / (2/3)</gadget>
<output>102</output>

<result>102</result>