There are three brothers, the eldest is older than the second (1/4), the second is also older than the third (1/4), and the eldest is older than the third by how much.
兄弟三人，老大的年龄比老二大(1/4)，老二的年龄比老三也大(1/4)，老大的年龄比老三大多少．
<gadget id="calculator">1 / 4</gadget>
<output>1/4 = around 0.25</output>

<gadget id="calculator">1 + (1/4)</gadget>
<output>5/4 = around 1.25</output>

<gadget id="calculator">(5/4) * (5/4)</gadget>
<output>25/16 = around 1.5625</output>

<gadget id="calculator">(25/16) - 1</gadget>
<output>9/16 = around 0.5625</output>

<gadget id="calculator">(9/16) / 1</gadget>
<output>9/16 = around 0.5625</output>

<result>9/16 = around 0.5625</result>