Adding a 0 to the end of a number results in a new number that is 909 greater than the original number. What was the original number?
在一个数的后面添上一个0，得到的新数比原来的数大909．这个数原来是多少？
<gadget id="calculator">10 - 1</gadget>
<output>9</output>

<gadget id="calculator">909 / 9</gadget>
<output>101</output>

<result>101</result>