There is a fraction, the sum of its numerator and denominator is 20, if 5 is added to both the numerator and denominator, the fraction obtained is equal to (2/3). What was the original score?
有一个分数，它的分子和分母的和是20，如果分子和分母都加上5，得到的分式与(2/3)相等．原来的分数是多少？
<gadget id="calculator">2 / 3</gadget>
<output>2/3 = around 0.666667</output>

<gadget id="calculator">(2/3) * 20</gadget>
<output>40/3 = around 13.333333</output>

<gadget id="calculator">(2/3) * 5</gadget>
<output>10/3 = around 3.333333</output>

<gadget id="calculator">(10/3) - 5</gadget>
<output>-5/3 = around -1.666667</output>

<gadget id="calculator">(40/3) + (-5/3)</gadget>
<output>35/3 = around 11.666667</output>

<gadget id="calculator">1 + (2/3)</gadget>
<output>5/3 = around 1.666667</output>

<gadget id="calculator">(35/3) / (5/3)</gadget>
<output>7</output>

<gadget id="calculator">20 - 7</gadget>
<output>13</output>

<gadget id="calculator">(35/3) / (5/3) / 13</gadget>
<output>7/13 = around 0.538462</output>

<result>7/13 = around 0.538462</result>