The decimal point of a decimal is moved one place to the right and is 4.5 larger than the original decimal. What is the original decimal?
一个小数的小数点向右移动一位后比原小数大4.5，原小数是多少．
<gadget id="calculator">10 - 1</gadget>
<output>9</output>

<gadget id="calculator">4.5 / 9</gadget>
<output>0.5</output>

<result>0.5</result>