Xiaoming went to Xiaofen to borrow books. Xiaofen divided all her books into 4 shares and lent Xiaoming 1 share and 6 books. Later, two children borrowed books from Xiaofen, and each borrowed Xiaofen's remaining books. In the end, the three borrowed the same number of books. How many books did Xiaofen originally have?
小明到小芬处借图书，小芬把她的全部图书平均分成4份，借给小明1份又6本，后来又有两个小朋友向小芬借书，每人借得小芬剩下图书的一半，结果三人借的图书本数一样多．小芬原来有多少本图书．
<gadget id="calculator">1 / 3</gadget>
<output>1/3 = around 0.333333</output>

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

<gadget id="calculator">(1/3) - (1/4)</gadget>
<output>1/12 = around 0.083333</output>

<gadget id="calculator">6 / (1/12)</gadget>
<output>72</output>

<result>72</result>