The minuend is 72, the ratio of the subtrahend and the difference is 4:5, what is the subtrahend.
被减数是72，减数和差的比是4：5，减数是多少．
<gadget id="calculator">4 + 5</gadget>
<output>9</output>

<gadget id="calculator">4 / 9</gadget>
<output>4/9 = around 0.444444</output>

<gadget id="calculator">72 * (4/9)</gadget>
<output>32</output>

<result>32</result>