There are some story books in the school library. After lending out 75% of the total, another 60 books are put on the shelves. At this time, the books on the shelves are 1/3 of the original total. How many books are there on the shelf right now?
学校图书室内有一些故事书，借出总数的75%之后，又放上60本，这时架上的书是原来总数的(1/3)．求现在书架上放着多少本书？
<gadget id="calculator">1 / 3</gadget>
<output>1/3 = around 0.333333</output>

<gadget id="calculator">75 / 100</gadget>
<output>3/4 = around 0.75</output>

<gadget id="calculator">1 - (3/4)</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">60 / (1/12)</gadget>
<output>720</output>

<gadget id="calculator">720 * (1/3)</gadget>
<output>240</output>

<result>240</result>