After the decimal point of number A is moved two places to the left, the result is 9.9 less than the original, what is number A?
甲数的小数点向左移动两位后，结果比原来减少9.9，甲数是多少．
<gadget id="calculator">100 - 1</gadget>
<output>99</output>

<gadget id="calculator">9.9 / 99</gadget>
<output>0.1</output>

<gadget id="calculator">0.1 * 100</gadget>
<output>10</output>

<result>10</result>