Choose any two of the four cards with 2, 4, 6, and 8 written on them respectively to form a two-digit number. If "6" can be regarded as "9", how many different such two-digit numbers are there?
从分别写有2，4，6，8的四张卡片中任取两张，组成一个两位数．如果其中的"6"可以看做"9"，那么共有多少种不同的这样的两位数？
<gadget id="calculator">2 * 3</gadget>
<output>6</output>

<gadget id="calculator">3 * 4</gadget>
<output>12</output>

<gadget id="calculator">6 + 12</gadget>
<output>18</output>

<result>18</result>