Cai Ming has a lot of books in his family. He lent these books to his classmates. He first lent 2 books and the rest (1/4) to A, and then lent 3 books and the rest (1/3) to B. , lent 4 books and the remaining (1/2) to C, and finally left 1 book, how many books does Cai Ming have in total?
蔡明家有很多书，他把这些书借给同班同学看，他先借给了甲2本和剩下的(1/4)，然后借给了乙3本和剩下的(1/3)，又借给了丙4本和剩下的(1/2)，最后剩下1本，求蔡明共有多少本书？
<gadget id="calculator">1 / 2</gadget>
<output>1/2 = around 0.5</output>

<gadget id="calculator">1 / (1/2)</gadget>
<output>2</output>

<gadget id="calculator">2 + 4</gadget>
<output>6</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">6 / (2/3)</gadget>
<output>9</output>

<gadget id="calculator">9 + 3</gadget>
<output>12</output>

<gadget id="calculator">1 / 4</gadget>
<output>1/4 = around 0.25</output>

<gadget id="calculator">1 - (1/4)</gadget>
<output>3/4 = around 0.75</output>

<gadget id="calculator">12 / (3/4)</gadget>
<output>16</output>

<gadget id="calculator">16 + 2</gadget>
<output>18</output>

<result>18</result>