(4/5) of a number is 120, find this number.
一个数的(4/5)是120，求这个数．
<gadget id="calculator">4 / 5</gadget>
<output>4/5 = around 0.8</output>

<gadget id="calculator">120 / (4/5)</gadget>
<output>150</output>

<result>150</result>