80% of a number is 16, what is 15% of this number?
一个数的80%是16，这个数的15%是多少．
<gadget id="calculator">80 / 100</gadget>
<output>4/5 = around 0.8</output>

<gadget id="calculator">16 / (4/5)</gadget>
<output>20</output>

<gadget id="calculator">15 / 100</gadget>
<output>3/20 = around 0.15</output>

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

<result>3</result>