There are 20 boxes of pencils, there are more pens than pencils (3/4), how many more boxes of pens than pencils?
有20盒铅笔，钢笔比铅笔多(3/4)，钢笔比铅笔多多少盒？
<gadget id="calculator">3 / 4</gadget>
<output>3/4 = around 0.75</output>

<gadget id="calculator">20 * (3/4)</gadget>
<output>15</output>

<result>15</result>