Beibei made 9 math cards, with nine numbers 1, 2, 3, 4, 5, 6, 7, 8, and 9 written on them, and put them on the table in reverse order, and randomly touched one to get a prime number How likely is
贝贝制作了9张数学卡片，上面分别写着1、2、3、4、5、6、7、8、9九个数字，打乱顺序反扣在桌子上，任意摸一张摸到质数的可能性为多少
<gadget id="calculator">4 / 9</gadget>
<output>4/9 = around 0.444444</output>

<result>4/9 = around 0.444444</result>