A number, after subtracting 6, the difference obtained is (2/3) of the original number, find this number.
一个数，减去6以后，所得的差是原数的(2/3)，求这个数．
<gadget id="calculator">2 / 3</gadget>
<output>2/3 = around 0.666667</output>

<gadget id="calculator">1 - (2/3)</gadget>
<output>1/3 = around 0.333333</output>

<gadget id="calculator">6 / (1/3)</gadget>
<output>18</output>

<result>18</result>