In a musical chair game, the person playing the music has been advised to stop playing the music at any time within 2 minutes after she starts playing . What is the probability that the music will stop within the first half-minute starting?

(Not for examination) In a musical chair game, the person playing the music has been advised to stop playing the music at any time within 2 minutes after she starts playing. What is the probability that the music will stop within the first half-minute after starting?