The younger brother is the older brother's age (1/2). 9 years ago, the younger brother was the older brother's age (1/5). What is the older brother's age now?
弟弟是哥哥年龄的(1/2)，9年前，弟弟是哥哥的(1/5)，求现在哥哥的年龄？
<gadget id="calculator">1 / 5</gadget>
<output>1/5 = around 0.2</output>

<gadget id="calculator">(1/5) * 9</gadget>
<output>9/5 = around 1.8</output>

<gadget id="calculator">9 - (9/5)</gadget>
<output>36/5 = around 7.2</output>

<gadget id="calculator">1 / 2</gadget>
<output>1/2 = around 0.5</output>

<gadget id="calculator">(1/2) - (1/5)</gadget>
<output>3/10 = around 0.3</output>

<gadget id="calculator">(36/5) / (3/10)</gadget>
<output>24</output>

<result>24</result>