If (3/5)a=(4/9)b, then a:b=((())/(())).
如果(3/5)a=(4/9)b，那么a：b=((())/(()))．
<gadget id="calculator">4 / 9</gadget>
<output>4/9 = around 0.444444</output>

<gadget id="calculator">3 / 5</gadget>
<output>3/5 = around 0.6</output>

<gadget id="calculator">(4/9) / (3/5)</gadget>
<output>20/27 = around 0.740741</output>

<result>20/27 = around 0.740741</result>