Answer for (a): 2/3
Step-by-step explanation:
In a uniform distribution, all probabilities are equal. In this case, the probability for being ‘x’ minutes late is each 1/30. Therefore, the probability that the friend is between 10 and 30 minutes late is 20/30 because we exclude the first 10 minutes. That can be simplified down to 2/3.
Answer for (b): 6 minutes
Step-by-step explanation:
The answer is simply 20% of 30. Since 30x0.2 is 6, the friend will arrive within 6 minutes.