There are 40 books in a batch, how many books are left after lending out (5/8).
一批图书有40册，借出(5/8)，还剩多少册．
<gadget id="calculator">5 / 8</gadget>
<output>5/8 = around 0.625</output>

<gadget id="calculator">1 - (5/8)</gadget>
<output>3/8 = around 0.375</output>

<gadget id="calculator">40 * (3/8)</gadget>
<output>15</output>

<result>15</result>