For a one-digit number, after removing the decimal point, the new number obtained is 50.4 more than the original number, what is the original number?
一个一位数，去掉小数点后，得到的新数比原数多50.4，则原数是多少．
<gadget id="calculator">10 - 1</gadget>
<output>9</output>

<gadget id="calculator">50.4 / 9</gadget>
<output>5.6</output>

<result>5.6</result>