A fraction is (4/13) after reduction. It is known that the numerator of the original fraction is 36 smaller than the denominator. What is the original fraction?
一个分数，约分后是(4/13)，已知原分数的分子比分母小36，原分数是多少？
<gadget id="calculator">13 - 4</gadget>
<output>9</output>

<gadget id="calculator">36 / 9</gadget>
<output>4</output>

<gadget id="calculator">13 * 4</gadget>
<output>52</output>

<gadget id="calculator">36 / 9 / 52</gadget>
<output>1/13 = around 0.076923</output>

<gadget id="calculator">4 * (1/13)</gadget>
<output>4/13 = around 0.307692</output>

<result>4/13 = around 0.307692</result>