The ratio of the minuend to the difference is 9:5, then what is the ratio of the subtrahend to the difference.
被减数与差的比是9：5，那么减数与差的比值是多少．
<gadget id="calculator">9 - 5</gadget>
<output>4</output>

<gadget id="calculator">4 / 5</gadget>
<output>4/5 = around 0.8</output>

<result>4/5 = around 0.8</result>