The difference between the numerator and the denominator of a true fraction is 3, and if the numerator is subtracted by 1, then (2/3) is obtained. What is the original score.
一个真分数的分子与分母相差3，如果分子减去1后就得(2/3)．原来这个分数是多少．
<gadget id="calculator">3 + 1</gadget>
<output>4</output>

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

<gadget id="calculator">1 - (2/3)</gadget>
<output>1/3 = around 0.333333</output>

<gadget id="calculator">4 / (1/3)</gadget>
<output>12</output>

<gadget id="calculator">12 - 3</gadget>
<output>9</output>

<gadget id="calculator">9 / 12</gadget>
<output>3/4 = around 0.75</output>

<result>3/4 = around 0.75</result>