There are three brothers, the eldest is older than the second (2/5), and the second is older than the third (2/5), what fraction of the age of the eldest is the third?
有兄弟三个，老大比老二年龄大(2/5)，老二比老三年龄大(2/5)，老大的年龄是老三的几分之几？
<gadget id="calculator">2 / 5</gadget>
<output>2/5 = around 0.4</output>

<gadget id="calculator">1 + (2/5)</gadget>
<output>7/5 = around 1.4</output>

<gadget id="calculator">(7/5) * (7/5)</gadget>
<output>49/25 = around 1.96</output>

<result>49/25 = around 1.96</result>