Teacher Wang has 5 keys, one of which can open the garage door. He took out one key and failed to open it, and then took another one out of the remaining keys. What is the probability that he can open the door this time?
王老师有5把钥匙，其中1把可以打开车库的门．他拿出1把钥匙没有打开，然后又从余下的钥匙里拿出1把，这次能打开门的概率是多少
<gadget id="calculator">5 - 1</gadget>
<output>4</output>

<gadget id="calculator">1 / 4</gadget>
<output>1/4 = around 0.25</output>

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