30% of a number is 140 less than this number, what is this number?
一个数的30%比这个数少140，这个数是多少？
<gadget id="calculator">30 / 100</gadget>
<output>3/10 = around 0.3</output>

<gadget id="calculator">1 - (3/10)</gadget>
<output>7/10 = around 0.7</output>

<gadget id="calculator">140 / (7/10)</gadget>
<output>200</output>

<result>200</result>