In a musical chair game, the person playing the music has been advised to stop playing the music at any time within 1.5 minutes after he starts playing. What is the probability that the music will stop within the first 15 seconds after starting?
Answer & explanation
Correct answer: option 4
The correct answer is Option (4) → 1/6
The music can stop at any moment of the 1.5 minutes, every moment being equally likely. So the probability is the favourable stretch of time divided by the whole stretch of time.
Whole time: 1.5 minutes \(=90\) seconds
Favourable time: the first 15 seconds
Probability \(\displaystyle =\frac{15}{90}=\frac{1}{6}\)