After removing the decimal point of a decimal, the number obtained is 4.5 greater than the original number, what is the original number?
去掉一个小数的小数点后，得到的数比原来的数大4.5，原来的数是多少．
<gadget id="calculator">10 - 1</gadget>
<output>9</output>

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

<result>0.5</result>