A number minus its (2/5) is 72, find this number.
一个数减去它的(2/5)是72，求这个数．
<gadget id="calculator">2 / 5</gadget>
<output>2/5 = around 0.4</output>

<gadget id="calculator">1 - (2/5)</gadget>
<output>3/5 = around 0.6</output>

<gadget id="calculator">72 / (3/5)</gadget>
<output>120</output>

<result>120</result>