What is the probability that any three-digit number composed of three cards marked with numbers 2, 3, and 4 is an even number?
用标有数字2、3、4的三张卡片任意组成的三位数是偶数的可能性是多少．
<gadget id="calculator">4 / 6</gadget>
<output>2/3 = around 0.666667</output>

<result>2/3 = around 0.666667</result>