Add 1 to the denominator of a fraction to get (1/3), and add 5 to the denominator to get (1/5). What was the original score?
将一个分数的分母加上1得(1/3)，分母加上5得(1/5)．原来的分数是多少？
<gadget id="calculator">2 / 5</gadget>
<output>2/5 = around 0.4</output>

<result>2/5 = around 0.4</result>