Divide a fraction, use 3 twice, use 5 once, get (2/3), what is the original fraction?
把一个分数约分，用3约了两次，用5约了一次，得(2/3)，原来这个分数是多少．
<gadget id="calculator">2 * 3 * 3 * 5</gadget>
<output>90</output>

<gadget id="calculator">3 * 3 * 3 * 5</gadget>
<output>135</output>

<gadget id="calculator">90 / 135</gadget>
<output>2/3 = around 0.666667</output>

<result>2/3 = around 0.666667</result>