With Xiao Wang's money, he can buy 15 pens, or 24 books. If he buys 10 pens, he can buy a few books for the rest.
小王的钱可买15支笔，或24个本，若买10支笔，余下可以买几个本．
<gadget id="calculator">1 / 15</gadget>
<output>1/15 = around 0.066667</output>

<gadget id="calculator">(1/15) * 10</gadget>
<output>2/3 = around 0.666667</output>

<gadget id="calculator">1 - (2/3)</gadget>
<output>1/3 = around 0.333333</output>

<gadget id="calculator">1 / 24</gadget>
<output>1/24 = around 0.041667</output>

<gadget id="calculator">(1/3) / (1/24)</gadget>
<output>8</output>

<result>8</result>