There is a number, move its decimal point one place to the left, 18 less than the original number, what is the original number.
有一个数，将它的小数点向左移动一位，比原来的数小18，原来的数是多少．
<gadget id="calculator">1 / 10</gadget>
<output>1/10 = around 0.1</output>

<gadget id="calculator">1 - (1/10)</gadget>
<output>9/10 = around 0.9</output>

<gadget id="calculator">18 / (9/10)</gadget>
<output>20</output>

<result>20</result>