Xiao Ming wanted to call Xiao Liang, but forgot the phone number for a while, only remembered that Xiao Liang's home phone number was 6878x635. What is the probability that he dials at random?
小明要给小亮打电话，一时忘记电话号码，只记得小亮家的电话号码是6878x635．他随意拨打，拨通的可能性是多少
<gadget id="calculator">1 / 10</gadget>
<output>1/10 = around 0.1</output>

<result>1/10 = around 0.1</result>