Find the ratio 2.5: (4/5)=how much.
求比值2.5：(4/5)=多少．
<gadget id="calculator">4 / 5</gadget>
<output>4/5 = around 0.8</output>

<gadget id="calculator">2.5 / (4/5)</gadget>
<output>3.125</output>

<result>3.125</result>