There is a true fraction, the difference between the numerator and the denominator is 18, and the denominator is 3 times the numerator, what is the true fraction? (solution by equation)
有一个真分数，分子和分母的差是18，分母是分子的3倍，这个真分数是多少？(用方程解)
<gadget id="calculator">3 - 1</gadget>
<output>2</output>

<gadget id="calculator">18 / 2</gadget>
<output>9</output>

<gadget id="calculator">3 * 9</gadget>
<output>27</output>

<gadget id="calculator">18 / 2 / 27</gadget>
<output>1/3 = around 0.333333</output>

<result>1/3 = around 0.333333</result>