For a fraction, the sum of the numerator and the denominator is 75. After dividing, the result is (1/2). What is the original fraction?
一个分数，分子和分母的和是75，约分后得(1/2)，这个分数原来是多少？
<gadget id="calculator">1 + 2</gadget>
<output>3</output>

<gadget id="calculator">1 / 3</gadget>
<output>1/3 = around 0.333333</output>

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

<gadget id="calculator">75 * (2/3)</gadget>
<output>50</output>

<gadget id="calculator">(1/3) / 50</gadget>
<output>1/150 = around 0.006667</output>

<gadget id="calculator">75 * (1/150)</gadget>
<output>1/2 = around 0.5</output>

<result>1/2 = around 0.5</result>