Among the prime numbers less than 10, if one of the prime numbers is randomly selected, what is the probability that the selected prime number is an even number?
在10以内的素数中，随机抽取其中的一个素数，则所抽取的素数是偶数的可能性是多少．
<gadget id="calculator">1 / 4</gadget>
<output>1/4 = around 0.25</output>

<result>1/4 = around 0.25</result>