The difference between A and B is 9.9. If the decimal point of A is moved one place to the right, it is exactly equal to B. What is A's number?
甲乙两数差是9.9，把甲数的小数点向右移动一位正好等于乙，则甲数是多少．
<gadget id="calculator">10 - 1</gadget>
<output>9</output>

<gadget id="calculator">9.9 / 9</gadget>
<output>1.1</output>

<result>1.1</result>