A number is first reduced by 1000 times, and then enlarged by 10 times, it is 0.9. What is the original number?
一个数先缩小1000倍，再扩大10倍后，是0.9，这个数原来是多少．
<gadget id="calculator">1_000 / 10</gadget>
<output>100</output>

<gadget id="calculator">0.9 * 100</gadget>
<output>90</output>

<result>90</result>