When Xiaohong was keeping accounts, she accidentally miscounted a decimal point, and the result was an undercount of 63.9 yuan. Do you know how much money she had?
小红在记账时，不小心点错了一位小数点，结果少算了63.9元，你知道她原来有多少钱？
<gadget id="calculator">10 - 1</gadget>
<output>9</output>

<gadget id="calculator">63.9 / 9</gadget>
<output>7.1</output>

<gadget id="calculator">7.1 * 10</gadget>
<output>71</output>

<result>71</result>