The latter term of a ratio is 18, and the ratio is (2/3), what is the former term of this ratio.
一个比的后项是18，比值是(2/3)，则这个比的前项是多少．
<gadget id="calculator">2 / 3</gadget>
<output>2/3 = around 0.666667</output>

<gadget id="calculator">18 * (2/3)</gadget>
<output>12</output>

<result>12</result>