If a two-digit number is divided by 9, the quotient and remainder are the same. What is the largest two-digit number?
一个两位数，除以9，商和余数都相同，这个两位数最大是多少．
<gadget id="calculator">8 * 9</gadget>
<output>72</output>

<gadget id="calculator">72 + 8</gadget>
<output>80</output>

<result>80</result>